Implantation dip?

Jessica • TTC since February 19th after being on the pill since May 2011.
I don't want to get my hopes up, but this could possibly be implantation dip. Today I am exhausted. I woke up, took my BBT and it was 97.7, went to the bathroom, and went back to sleep. I woke up 3 hours later and retook my temp and it was 98.3. I know we will see what happens but one of my apps says my af is due on cd34 while the others say cd30. I typically have 28 day cycles but it looks like I ovulated late. What do you guys think?