you are describing a FENTAYL or some analogue of FENTAYL overdose that caused this. only you know if that is true or not. unless you have epilepsy which could cause a mild seizure when you were out not allowing you to breathe..... sounds like an analogue since you are still alive..... most FENT analogue's have a very short half life <60 minutes...... so your brain remembered to breathe once the receptors were no longer hijacked....... tell someone next time and keep naloxone in your pocket at all times. it is free at all hospitals, and should be sold OTC in my opinion.
I am a heroin user as well. although I've been clean for 70 days, my anxiety is horrible when the doctor takes blood from me. I'm not sure if my anxiety stems from the needle and my past or if it's the blood itself. Either way, whenever I have a panic attack, I get heat flashes, sweats, tunnel vision, nausea, stingling of the skin, and my lips turn a dark blue color and my skin turns grey. I've never had my lips turn blue before and it totally freaked me out. They were cold to the touch and my doctor said it was because I was about to faint.
I know nothing about heroin, veins or blue lips but this link says a side effect can be collapsed veins. You need a professional to make a diagnosis though so take this post with a grain of salt. Some nurses post on this forum so you can wait for one of them to see this and respond, or try another forum to see if you can get a quicker answer to the blue lips query. Good luck.
http://voices.yahoo.com/facts-heroin-heroin-symptoms-use-8636463.html
Anxiety doesn't have anything to do with lips or coloring. It gives you adrenaline to help you in a fight or flight situation, so you can perspire, heart beats a bit faster and stuff along those lines. Possibly your lips had that coloring before but you didn't notice. How old are you?