Pregnant?

So I've been on birth control for a week and a half now, and have had sex with two guys. On the first day I started the pill, I had sex with a guy with no condom and he pulled out (yeah I know not the best decision), and one with a condom. Also I recently had a yeast infection and have since taken a pill to get it treated. I also have been taking antibiotic pills. I have been experiencing pink mucus discharge, but it's only a day or two before my period and since I started new birth control pills, I was told that pink spotting was normal. I have also felt a little nauseous but I also haven't been drinking enough water with my meds like I was told so that may be the reason too. I haven't experienced any other pregnancy symptoms.

Has anyone else experienced these? I just feel like my body is freaking out because of all the drugs.