Not sure, but I think I may be pregnant. Anyone ever experienced EARLY signs like these?

My fiance and I had Thursday (9/3, 6 days before my expected period) night. We did not use protection and he did "go" inside me. The next day in the afternoon, I started to have gy-like cramps, a little flatulence/constipation, and my began to get somewhat tender. I have noticed some lower back pain and abdominal pain as well. This has been going on every day nonstop. My expected period is tomorrow (Wed 9/9). I know it can be hard to tell if these are early signs of pregnancy, especially since I'm so close to my period. Every woman's different and I was wondering it there are any other women (pregnant or mother) who did in fact experience these symptoms. I do hope that I am pregnant and I'm just worried I'm not is all. Thanks :)