Hi I'm Concerned That I Might Be Pregnant, I Don't

Hi I'm concerned that I might be pregnant, I don't remember the exact day of the beginning of my last period, but is between the 01-05 AUG, I had sex the 12th and I'm sure he didn't cum but is the first time I don't use a condom, the 15 we had sex and he came outside but I took a morning after pill that same day and we had sex again the 17th and he came outside as well. Since sunday (2days ago) I've been experiencing some bleeding is between dark and bright red, with some lower abdomen cramping yesterday but I don't know it its because I'm worried. I'm confuse if the bleeding is because of the morning after pill or it can be implantation bleeding. Do you think I could be pregnant?, Can I take a urine test today?