Sore abdomen

Hi everyone. I have been ttc for about 3 months now. My AF is due this Sunday. I have been getting symptoms like crazy. I've bad 3 kids, I should know my body by now, we'll enough to figure out if I am pregnant or not. If I am not this time, then I am at a loss lol. Anyway, yesterday, I woke up with a pain in my mid to lower belly. It feels like a did about 50 crunches. Everytime I lay down and lift up, it hurts. I looked up some things about this and found that it happens a lot with women who are about 4 weeks or are about to find out there pregnant or not. Anyone else getting anything like this? It's not cramping. It's sore muscles I think. I didn't do anything strenuous or work out Or anything. When I lifted the heavy dressers I bought last week, I didn't even get this then. I'm hoping this is just another sign of pregnancy lol. I will test on Sunday. I'm hoping it's positive!