Hey everyone, I just joined this forum so it's nice to meet all of you!

I hope this is the right section for this, and as a little warning I'm going to go into detail about stuff and it might be a little TMI. Just letting you know before reading.
I've been taking Microgestin Fe 1.5/30 for over a year and a half and I take it everyday, however some days I'm a couple hours late. I've never had vaginal intercourse. Anyways, right now I'm supposed to be on my period (it's my third day taking the brown pill and usually I start after two) but it isn't here. I've had a bit of cramping but I'm having this stringy brown discharge that I've never had before and it's only when I wipe that I notice it. Earlier today I had a lot of white discharge, but now it's mainly brown.
I'm afraid that I'm pregnant because a couple days ago my face broke out in acne, I had to urinate constantly (even though I didn't seem to be drinking more) and I gained weight. This could also be PMS or the fact that I haven't been washing my face and I tried a new moisturizer which apparently has a lot of oil in it, and I've been trying to gain weight for the past couple years. My mom jokingly said I'm pregnant, and that freaked me out.
As far as sexual activity, every time I do anything with my guy I'm always wearing underwear and a pair of his basketball shorts. He's ejaculated on my stomach and I'm not sure if I sat up before wiping it off. There also might have been a time when I noticed a wet spot on the shorts when I was putting back on my clothes, but I don't think it soaked through. He's also "dry humped" me, but again I was wearing the shorts.
I've been doing tons of research online and I don't know if any of his sperm might have gotten on my leg and then slid into my vagina or not. I have an anxiety disorder so I tend to worry and obsess about things, and I've been so worried! I'm on some medications (Prozac and Xanax) but I don't think they should make the Microgestin less effective. I take a Xanax whenever I go to his house though, which is about every week or two. I wouldn't be worried except for the fact that my period isn't here and I've never had this discharge before. Please help me and let me know what you think, if there's a chance I'm pregnant or not. Thank you so much to whoever reads this!