a little confused, can someone give me some answers please

 Okay, let me start out by saying that I'm not pregnant yet. I've been in this group since I was pregnant before though. I like reading about everyones journeys.

I'm so confused. Today is CD10. Yesterday I had a little ewcm. I also felt a very sudden sharp pain in my abdomen while I was laying down last night. Today I had a lot of ewcm, only once when I wiped. I have terrible cramps and a horrible back ache. I started opks today because I was told to start on day ten. I tested around 11 this morning. There was a light line, I didn't have to squint to see it, it was there indicating neg though since it wasn't as dark or darker than the control line. I then Tested at four pm with a lighter line and 7pm with no line. Is it possible to have already o'd so early in my cycle and caught  the last of my surge on the test after I o'd?? I typically have 28 day cycles.

Forgot to add my cm is next to none now :/