Can I be pregnant?

[nicki2016]

I have been having sore breasts for the last two weeks. Urinating a lot and so I thought I was pregnant. I took a pregnancy test early on Monday and it came out negative. Then on Wednesday I started having a really bad headache on one side of my head. The left side. And I thought sleeping it out would make it better, which is always the case for me when I have one, but not this time. It's Friday and I still have the headache. Last night my period came (it was supposed to come on Saturday so it was a couple days early) and it was heavy. Usually for me the first day is light and it gets heavy on the second day, but not this month...and it's still a little heavy today. I didn't have cramps or vomited.
I'm on birth control pills even though I missed two days and took the pill on the following morning. Could I be pregnant even though I got my period? My period came early and that's not very unusual for me, it has happened before. Could this be implantation bleeding?
Please answer the best way you can with the information I posted. I'm 29 by the way and a baby would be very welcomed to our lives if this was the case.