Can someone help?

I’m 4 days late on my period as of today. I’ve took 2 tests, different days both negative. I had sex on the 6th and the 7th of April! (Both very high days according to my app.) I’m 17dpo, and last night, very late I went to the restroom, wiped and have a tiny amount of pinkish color blood, not a lot, and when I went to wipe the second time it was a little less than the first time. I thought maybe AF was coming, but I won’t up this morning with absolutely nothing. Now, I know sperm can live up to 5 days, my question is, could implantation be happening right now?

Also, I had sex on the 22nd or 23rd, I didn’t get a period, so I couldn’t get pregnant from that time around correct?

All day, I’ve been having this CM, is it normal? I usually never have this much, but it’s been all day long.