I've been on a variety of meds growing up for anxiety/depression problems. They didn't do shit for me except make me tired. My friend was prescribed seroquel which is retarded and basically numbs your feelings. Sure you don't feel upset, but you'll also do harmful shit without realizing the consequences. I was prescribed paxil (SSRI), prozac (MAOI), and xanax (benzo). None did a damn bit of good.
I over-analyze every fucking thing so can feel you on that. It actually has caused me some insomnia problems because I can't sleep due to my brain constantly racing thinking about shit. Pot is no longer enjoyable like it used to be after the "peak" when I'm stoned but able to focus. Once I start analyzing things, stoned, it usually builds my anxiety or makes me depressed. If I smoke anymore, I prefer to smoke with friends that will distract me. Funny thing -- a lot of the shit I want to change about life while I'm stoned seems like a really good, beneficial idea. Once I'm no longer stoned, I think the opposite. It's hard to determine which is best when they both sound "correct," but strangely enough my "high" reasoning is usually what most would consider the best advice. Too bad that at the same time it makes me miserable...
Anyway, the "keep yourself distracted" suggestion was a good one. If I keep enough shit going on, I never have time to analyze and get disappointed or depressed. You can try pot, it may help and it may not. I don't suggest prescriptions. IF they do you any good, they're just masking the problem and not solving it. Unless you truly have some sort of chemical imbalance, it won't do shit to improve your life. I realized during a great trip one day that if I don't like how my life is going, I'm the only one that can change it. Simple concept but took me forever to realize until I jumped in the k-hole and looked at everything at the most basic of levels.