He's 16 I'm 17 and we could be pregnant

It was my first time having sex but not his. We did it unprotected and he said he pulled out in time but I read it takes a lot of practice and knowledge of your body to be good at pulling out. It was a couple days before I was supposed to get my period but it didn't come. I'm on a very low doce of the pill but I don't take it at the same te and I forget days so I feel like it's pretty unaffected. And it's been a week and this weekend I experanced brown liquidy discharge followed by blood that looked like my period but the blood was really dark. I read that the brown discharge could be implanting but I'm also googling way to much but I have a gut feeling I'm pregnant is it to soon to take a test or should I go to the doctors and have them do a blood text?