Implantation?

I went to the bathroom on my lunch break today and had two small spots of brown blood on my underware. I have a week until my period is due. Could it be implantation bleeding? I've also had super sore boobs like they hurt to touch. I walk in the hall at work and almost cross my arms over them. And I've had to pee a lot more but I've been drinking tons of water from always being thirtsy. I ovulated a week ago.