I just started birth control. This is my first month. I haven't missed any pills. I am experience frequent urination and food cravings. I had sex once. I also had my period but it was darker than usual and very light. I was wondering if these things can be caused by birth control, or do they mean I'm pregnant?

Birth contol does not prevent pregnancy effectively for a whole month or two after you start taking it, so it may be pregnncy if you did not use other protection. Call the doctor and ask what he or she thinks, it could be the BC messing up your cycle, it could be pregnancy, it's impossible to just know.

When prescribing a new birth control method you should have been informed to use back up protection for at least 2 weeks. Even then, birth control pills are only about 97% effective (trust me, I have a daughter from when I was on the pill).

If you have had your period I wouldn't stress too much. While it is not uncommon to have periods early in pregnancy it doesn't happen all the time.

Your change in cycle... flow, length etc is most likely related to you started the pill. The pill causes changes in your cycle.

You can do basically one of two things. Wait until next month and see if you get your period like you should or take a HPT.