I too began smoking and absolutely loved it. Then I started smoking very regularly and had a lot on my mind at the time. I think I was getting stoned and thinking too much and got into a routine of doing so which in turn led me to have panick attacks. I stopped smoking 4 months + and started again about three weeks ago and it has been a wonderful mental vacation everytime from all my work. I too can symphathize with you about OCD it really is a pain in the ass. Something that has worked for me is when you begin feeling a repetitious thought process or feel like doing something to release that stress like checking your pulse just tell yourself you will do it later and believe it. If you can succesfully do that there are a number of cognitive thereapy steps you can work through to release that overall anxiousness. You may want to speak with a therapist that specializes in anxiety and does not just want to push medication on you. As for now when you truley feel anxious take 10 deep breathes slowly and take it by the hour with each hour being better. And taking one of those Xanax certainly won't harm you if you ever truly feel you need immediate relief. Good Luck