If you're worried about your mom coming home early you probably won't have a good trip.
This. I remember being about OP's age, made up some excuse about school/college being closed for the day and getting a very angry phone call after just coming up on the stuff as she'd driven past the bloody place and saw that it was most assuredly, not closed. This was probably my first real experience with acid too, as the previous blotter was utter shite.
Luckily I convinced her I was heading into college/school and figured I'd just stay at home and hope she'd be stuck at work, however despite the fact that there was a very high chance she would not return to check if I was still at home every minute I spent in that house was complete and utter hell. After about twenty minutes (which felt like hours) and a few shots of rum (didn't help much) I decided to leave the house and chill out at a friends, or if he wasn't home, go for a movie or something where I'd be out of that house (and in my mind at the time, safe).
Within the first few minutes of leaving the house all the worry, tension and bad vibes went away, I sat at a bus stop for about twenty minutes admiring how awesome the horrible pissing rain was. In the end everything worked out, all was well, but if I'd stayed in that house I'd have gone insane.
Where you trip and how safe you feel in that area when tripping has a
huge influence on how your trip will turn out. There are no bad trips, only difficult trips and every trip, every journey will come to an end, just like climbing a mountain or running a marathon, getting to the end of a difficult trip will probably leave you with a more rewarding insight, though if you're not used to running marathons, or climbing mountains, you should probably start small. Get to know the acid and let it get to know you, the anxiety (which will mount to dread and terror) of your parents catching you tripping (I'm assuming you think they'd be pissed off, though they may just be supportive if they know what's going on and aren't members of the anti-drug cartel) will stop you from getting any satisfaction from the trip at all. If you can leave the house when they come home, you could do that, but if it's putting you off so much that you're asking on here I'd suggest you trip elsewhere entirely, or trip another day.
If you're looking for a magical trip-aborting substance, well there isn't one that will remove your trip and leave your sober and clear headed as you were before dropping acid. If you want to soften a harsh trip, benzodiazepines are usually the way to go. If you are stuck in a trip that is so horrible you'd rather it just go away and never come back, I'd recommend taking GHB/GBL, though only after practicing first. GHB/GBL can induce a very deep, coma like sleep if you get the dosage right and it has a wider therapeutic index (difference between effective and potentially lethal dosages) than similar drugs (barbiturates, propofol, etc) this sleep lasts for about four hours and for the first two nothing and nobody will be able to wake you, GHB/GBL knockout doses are still very dangerous and I'll probably get shouted at for even suggesting them, but they are probably the most effective and least deadly way to completely end (you'll still have crazy dreams) a trip.
If a trip is going bad, follow this formula
1) Do I feel safe where I am? If not, would I feel safer moving elsewhere? If moving elsewhere is even more daunting, is there anything you can do where you are to make things feel safer and more familiar. If you like playing guitar, start playing it, if you like playing computer games do that ('polynomial - space of music' is an amazing trip game).
2) If there is nothing you can do to get rid of the anxiety; take a benzo, booze works too, though causes much more nausea. I'd say opiates take the edge off too, but opiates are dangerous, addictive and probably harder to find for you than benzos are. The therapeutic index for benzos is much wider than that for opiates and if you're having a
horrible trip you tend to grab as many pills as you can and shove them down your throat, with benzos this will probably just knock you out like GB, with opiates, depending on what opiate and which strength this could knock you into a (very) early grave.
2.5/3) If the benzos aren't working you can't really take GB as the potency of both drugs would be multiplied to an amount that it could be very easily lethal, 4mg diazepam along with a low dose of GB knocked me clean out. You really need to make the decision on whether you want to dull, or abort your trip at step two and either go for the benzos/gb/opiates (listed in order of safety, safest first) and pick only one if you are inexperienced with them even if you do have prior or even significant experience with either of those three I'd still suggest you stick with one, I've nearly died at least once because of a benzo+opiate cocktail and again from taking way too much GB, each time I was highly experienced with what I was doing, but reckless; tripping and anxiety heightens recklessness, do the math.
4) This is only reserved for the worst of trips and it probably won't be you who gets you dragged off to the hospital, I've only ever seen it happen once and it was when a friend of a friend took like 2 tabs of blotter, then 14 more, terrorized his neighbourhood and had to be driven to hospital by his parents. You never want to reach step 4.
Sorry if I'm rambling a little, I've never been good at getting writing to come together all in one go, expect to see many edits.
PS: You might want to read up on Tim Leary's system of set & setting. Personally I'd spend a day preparing for trips that I have on my own, when tripping with others it's usually more spontaneous.
im getting some shiva blotter this weekend,im going to be home alone until my mom gets home and im planing to trip i have taken some very strong avenger blotter before and alice in wonderlands too. this will be my first solo trip and im worried about a bad trip and/or my mom coming home early. is there anything i could do to prevent a bad trip because there will b noone with me and i will not have access to my phone to call a freind if something does happen . i will have access to internet xbox guitar ect.. can someone please help me out here - spaceraider 
