What Causes Cramps And Sore Breasts?

Hello, I have had 2 miscarriages both around 6 weeks (one I found out at 9, and one at 11 weeks). One in 2004 and another in 2008. I then never had a period since the one in 2008 for more than a random day every couple months if that. I had some slight spotting early in July, and believe I must have conceived around July 30th. making me roughly 6 weeks pregnant.? My levels dropped very quickly with both losses pretty much as soon as i found out I miscarried and did not have much for pregnancy symptoms. I have the odd cramp and incredibly sore breats right now, should I be going to see a doctor right away for progestrone shots? or should i wait it out and see if I even carry thru the first trimester?