To paraphrase/piggy-back off of what Dave said, Poppa:
The absolute best thing you can do right now is quit smoking crack (and don't start using an alternate route of administration for it or other drugs), start eating better and exercising (remember: baby steps. You're probably not going to be able to run a mile the first time out.), and allow 8-10 hours for sleep each night.
In my opinion, the first thing you need to do is quit the crack and drugs in general. Then you will have a clear mind to realize that not all these medical concerns plaque you. I thought I was going insane when I was heavy into drugs--I started seeing shit while at work (I worked the night shift--Ever see The Machinist? Not quite as extreme as that, but just as scary). I started thinking things that were rather irrational, too. I remember posting something on BL that actually got closed down by the mods, saying I needed to quit the drugs and go see a doctor if I still felt that way after quitting drugs.
And guess what? I quit the drugs (not all at once, but some at one point, some at another, and the rest at another time) and got my diet/life back on track, and a little more than a year later, I am a changed person, for the better.
Best of luck, Poppa. Keep us updated. :)