Ever since I bought my car it has been doing the same. Before it was every other month and I thought I left a light on or something, but now it is every time I drive it for more than 10 minutes. My battery starts draining but specially if I turn the A/C on. I don't know if it is the alternator or some problem with the A/C. I changed my battery a few months ago and now it is back to the same thing. Any suggestions.

 

your alternator is probably shot. autozone can test it though. it could also be a bad ground or connection