Ovulation tests all over the place.. HELP

My chart was showing me ovulating this whole past weekend and last week. My cm was dry so I knew that it was wrong and just kept using digital ovulation tests. I got one positive test last week and then the rest of the days I was dry and the tests were negative. I took one today bc I’m coming up in my last days according to my chart and I got a positive today. What’s up with that.. we didn’t have sex last night bc we were tired but we did the other nights that I was dry and got negatives. Now I’m worried.. I hope this makes sense.. I’m worried I may get pregnant