hey, from what ive heard ur just sketchin, im with birdgirl on the quitting smoking cigarettes thing, i smoke them myself and have for the past 5 or 6 years, and im 17, -i want to quit and wish i had never started.
if the main reason you started worrying was because your heart races, dont worry, seriously, everybodys blood pressure and heart rate increases when they get stoned, and i often worry a little when i realize my heart is pounding quickly too, but its nothing to worry about, when your heart rate increase your blood pressure goes up and makes you feel dizzy, (which is pretty much how you get stoned amongst other things,) and smoking ciggarettes does the same, it takes 20mins for your blood pressure to revert back to normal after smoking a ciggarette, all i can say is DONT WORRY! GET HIGH! lol and quit the cigarettes, lol they suck,

-peace and good luck,

(blood pressure sucks ass, everytime i get high, i go to stand up and everything goes black and i end up falling over where the blood pressure in my eyeballs is way too much,) - oh, and dont start worrying about your eyes exploding haha...