The intense rush is the 6-MAM metabolite which hits fast and hard. The remaining high (the 'legs') is mostly due to the action of the morphine metabolite. You say you're an addict, so you have some experience: are you saying lately the rush is hitting harder than in the past? Fentanyl as a cut will result in more intense rush, way shorter legs.
As for your dosing, this isn't HR, just an observation: it's harder to overdose on heroin than people tend to realize. The dosage range is large. People OD when they're used to shooting 6 of these bags per shot for a nod, get a bundle of different dope and start with 6 bags that could easily be three times as potent.
Nodding or blacking out ~10-30 seconds after administering a shot is more of an immediate severe overdose situation. The less acute (equally serious) overdose may not lead to intense nodding/unconsciousness for 30-60 minutes, around the time my normal nod sets in after a good shot, and in that situation it's best to stay awake and breathing. Next time you feel like you're in one of your better nods, check your heart rate and see how well you're automatically breathing. As you go higher, breathing becomes an act of will and not so involuntary, and I would reconsider my dose if I began experiencing shallow breathing or nodding in a way that might keep me asleep and unable to "choose" to respirate
Sucks supplementing shots with bumps or even more shots since there's a bare minimum dose needed for a satisfying, worthwhile rush. If you're sure your dope doesn't have fentanyl in it start dosing a little higher so you don't have to supplement later. Your caution is good, but one shot, one experience is so much nicer than bumping to get there or further puncturing veins to only administer another 20 mg to get "just right." For what it's worth, my "good rush" functional dose is exactly half of my "good nod" dose. That's quite a wide safe use range therein, and with cautious sampling of new product to derive a purity estimate from, and a milligram scale for each dose, you should be able to get the perfect dose every time. Dosing accurately so the rig is perfect the first time every time is key, but I find in doing so I'm much less likely to impulsively redose and end up doing three or four shots on a day where I was just planning on doing one. There could be positive disciplinary side of that
Your stuff being cut with fentanyl is pretty unlikely as it isn't that common to do, but it being fent-laced certainly gels with some of what you say, about the intense initial rush and weaker short-lasting high after that. ODing on fentanyl would provide a more significant rush and more immediate respiratory failure, a reason to be mindful of dosing high upfront (in one shot). I find hydromorphone, oxymorphone and fentanyl to have an intense, ass-kicking rush, whereas heroin's is calming, quiet and not overpowering.
Maybe I'm being over-analytical, though. You said you only recently went from snorting H to IVing it. The rush from the 6-MAM is MUCH more pronounced and more obviously a second high separate from the long-lasting morphine high when IVing as opposed to snorting. The 6-MAM hits so fast and feels pretty much all gone after 60 minutes, then you have 4-5 hours of a strong morphine high to enjoy.
A missed shot feels like a dull bruise that can burn a bit depending on the substance(s) left behind. It's extremely easy to treat the immediate issue, getting the shot into you fast. Whenever you missed will red and eventually the solution will float to the top of your skin, possibly having migrated some, unless the shot was too deep to do so. Go to the sink and get the water in the sink as hot as you can possibly bear. Put your arm or wherever the missed shot is in the sink and run hot water over it for 5 minutes solid, then massage with a hot compress for another 5-10 minutes. One time I did this while staring myself in the eyes in the mirror. I missed the whole damn shot, so my pupils were normal, and I watched the drug sink in in a matter of minutes, pin-point my pupils and put me close to nodding
P.S.: Someone is more likely to accidentally overdose when supplementing doses when they're already high than a cautious user with known product that has been weighed so you're dosing +/-5mg of your known good dose, a small enough amount to increment by that will let you know without killing you when you're approaching OD territory. I doubt your max dose ever even gets near it.
![:\](https://bluelight.org/xf/BL_Images/Orig_Emoji/wrygrin.gif "wry grin :\")
