I think anxiety meds might be the answer.
meds should only be a last resort man. they're a short term solution for a life long problem. life is hard and sometimes it's perfectly logical to be anxious - but you're also perfectly capable of overcoming it on your own. and if you can do it on your own then why walk with a crutch?
I just made a thread today about overcoming panic attacks when you're smoking so as to calm down and enjoy it more, I suggest you check it out. it all comes down to diverting your attention away from the negative/draining and on to something positive/energizing.
as for the kottonmouth, keep a drink with you when you smoke as well as some snacks that have a high water content like fruit (melon, pineapple, grapes, etc). take smaller hits.
nasal congestion I don't know. I drink herbal tea or hot apple cider when I'm sick and that usually helps me hack up the phlegm.
and the heartbeat...
I used to notice it when I first started smoking. just tell yourself that you can't overdose, that the chances of you having a heart attack from being too high are pretty much nonexistant, and just sit down and meditate for a few minutes.
good luck and please give the natural way of life another shot before you allow mr pharma to bait and hook you like a trout