Am I bleeding because of my hymen or the use of Postinor 2?

Patient: I had sex for the first time two days after my period finished (he didn’t go in the whole way and he pulled out before ejaculating). In lieu of using a condom, I took Postinor 2. A week later, I had sex again (but again, it didn’t go in the whole way and no ejaculation). Immediately after, I started to bleed. I first assumed it was my hymen but the blood was brown/red and had not subsided the next morning. It is now the next afternoon and I’m uncertain as to what has me bleeding. Whether its the Postinor 2 effecting on my body, whether its my hymen bleeding away slowly, or if it is my period two weeks early (perhaps brought on by taking the pill). One thing I hope is I am not pregnant. Please, what has me bleeding? Thank you.

Symptoms: Brownish/red blood coming from vagina, cramps