Any suggestions

My periods are usually on point between 20th -24th of each month. Last month June my period came on 24th to the 28th. I had sex on the 28th and 29th but I guess my period wasn't OVER completely because I bleed a day or 2 after the 29th. Fast forward to July I took a clearblue ovulation test got a solid happy face on the 6th had sex that same day. Now 3 or my 5 apps are saying I'm 8 days late for my period and the others are saying my 3 days. I did take a test this and it was bfn (dollar tree test). I'm thinking I should just wait til my doctor appointment on the 3rd and hope for the best but my question is has this ever happen to any1 before? I never missed a period like this unless I was pregnant, I know its still technically a few more days in this month but this is NOT like me I usually know af is coming because I get cramps and ill spot this month I got cramps but NO SPOTTING..... Should go get a digital test or just plan wait til the doctor visit??????