Do you think I missed my fertile days?

So last month I had a 35 day cycle. Right now is day 31 for me. So I could be expecting AF anytime. If it comes then I will start Femara if not then all the better. Anyway, so we BD on CD12-19, 24 and last night. I had my wisdom teeth removed on the 20th and was out of the game for a few days lol. Anyway, so right now my cervix is really high and it seems like it is getting softer everyday, i am not sure if that means AF is coming or if I may be getting close to a BFP. I tested twice last week, yesterday and today. All were BFN's. I know that i could have tested to early and I also didn't use FMU. Also today, after I wiped once i noticed some mucus on the TP with a string of blood on it. Just one tiny little string and there has been no flow. Could this be implantation? When does implantation usually occur, like how manhy days before AF? It could also be because I have been checking my cervix. Anyway ladies, what do you think?