my 2 cents
Yeah you'll know if you hit any arteries...you can potentially bleed out.. If this hole youve poked does not close up. Not always the case.. But definitely possible. I see lots of users, tie off way too tight, this can also have an effect on blood pressure. You only want your tie to be slightly snug. That way your veins plump up, but your arteries still flow. Otherwise how can you register..your cutting of circulation, and always let your tie loose BEFORE you start pushing that plunger. When you poke.. Try to have the hole in the needle tip facing up at the ceiling, so as to register and penetrate a little easier, and to prevent air being trapped upon insertion. Most people don't think about the tiny things.. For instance, another thing I learned from a book.. When you finish your shot and ur done pushing the plunger all the way down.. Don't pull out..even though your done pull back a tiny bit (maybe a quarter inch, or just under) one last time and push that back in as well.. Because in all actuality, there's a tiny like bit of drugs (and blood)still stuck in the needles tip.. So when you do that last tiny pull and push.. It gets the very last little bit out. That's why if you've ever taken a perfect shot (found the vein, registered and got everything in)it still has the teeny tiniest little sting when you pull out.. Cuz the drugs left in the tip of the needle, essentially cause a itsy bitsy miss.. This is why old drug vets have "track marks" or little tiny bumps like scar tissue or what not as well.. So doing this last push and pull.. Savors every last little bit of drugs.. Rids the needle tip of any leftovers (eliminating any painful sensation of a mini "miss") and prevents any visual abuse marks and indications of abuse. Also wherever you poke.. Always point TOWARDS your heart.. Go WITH the flow.. And just for the record, fevers accompanied with other extreme discomfort, could possibly be "cotton fever" most people think that cotton fever is a micro fibre of cotton lodged in your syringe, that accidently gets injected into your bloodstream. This is not the case. It's actually a batch of cotton that has been contaminated with a bacteria, or microbial Germ of sorts living in the cotton.. That you happened to come in contact with when using it as a filter to draw up.. So it's out of your hands.. You can buy a brand new thing of questions tips or cotton balls or whatever, and be super safe and clean.. And still accidentally use that unlucky piece of cotton as a filter.. Hope some of this helped