Non-Hormonal Birth Control?

Goldie
When I was 16 I was on birth control for about a year. The terrible side effects I had greatly interfered with my daily life. I was an emotional roller coaster all of the time and completely lost my sex drive. 
I am now 19 and have a boyfriend whom I have sex with quite often. We always use a condom, but I don't like the idea that I have no backup if something with the condom goes wrong. Due to my previous experience I am not willing to go back to a hormonal birth control method. Does anyone have any experience or advice on non-hormonal forms of contraception? What works for you? I've considered tracking my BBT...how well does that work in preventing pregnancy? Any advice is greatly appreciated.