Late period or pregnant? Help!

My husband and I are 27 and not TTC. Our DS will be 2 in a week and we aren't ready to bring a baby into the mix. My cycles are anywhere from 27-31 days, 28 days being the average. We have used the pullout method for a year and a half prior to conceiving our son and have continued to use it since he was born. I know that it isn't fool-proof and that we chance pregnancy each time, but it's what's worked best for us as a couple. I pay close attention to my cycles and we basically abstain during my ovulation week, and remain super careful the rest of the time. Since my cycles are irregular, I never assume I know my actual ovulation date. We had a spur of the moment session on day 14 in my cycle and we quickly realized we shouldn't have messed around. He was very careful, as always, but now I'm on day 30 and AF hasn't showed up. On day 25 I started having cramps and expected AF to be even earlier this month. I've continued to have cramps off and on since then. This morning day 30, I woke up at 5:30 with bad stomach (not uteran) cramps, this occasionally happens before my period. I got up and between 5:30 and 7 I had loose BM stools 3 times, this is also not out of ordinary before AF shows later in the day.  I suddenly thought maybe this is early pregnancy symptoms that I don't remember from almost 3 years ago. I ran down to the Dollar Tree and got two different pregnancy tests. I came home to take them, I had already urinated earlier, but hadn't drank anything since last night I'm not sure if that matters when it comes to "first morning urine". Both tests were clearly negative and I went on about my day. This evening I'm having cramps, pain around my left ovary, and watery CM (enough that I keep thinking I'm starting), but no AF. Should I wait it out and see if she shows up and test again next week? I had zero PMS synptoms before finding out I was pregnant with my son, so I don't feel like I can compare the two situations since I've felt like AF was coming this whole week. I have dealt with cysts on my left ovary for close to 10 years so that has crossed my mind. Endometriosis is also VERY common in my family. As a matter of fact, my grandma, mom, aunt, and cousin all needed hysterectomies before they were 30.