please someone who know this, help!

Okay so i know I should really ask a doctor, and I will, but I kinda just want a different opinion about this. 
I had sex 4 days ago, then again yesterday with a different guy, the second guy was a little bigger than the other. Two before I had sex I noticed some brow stuff coming out of my vagina, no pain and not a lot of stuff, it was just staining my underwear. Then after I had sex the second time there was even more. The this morning there was a lot more, it looks like clogged blood, like on the last days of your period it's thick and darker. Now, later in the day, I see some thin blood, red, and my vagina is a little sentive/sore. 
Fun facts that might help.. Im in the middle of my cycle. eve says 3 days until my fertile window opens. 20 days from my next period. I'm 17, hadn't had sex for 3 years until 4 days ago. My cycle length is around 40 days. 
I used protection both times, I'm thinking it could have been old blood that was stuck and released by the penis or I got hurt somehow. 
I did some research and it said it could be pregnancy or an infection, or dryness. I'm more worried about the pregnancy part so what do u guys think? It's only been 4 days and it only started getting worse after the send time. 
Help please?!?