TMI- is this implantation?

Soo af was meant to come yesterday I’ve had no symptoms what so ever I’m always regular so I know when I’m due to come on! This is now my 2nd day with no show of af when I went to the toilet yesterday and wiped I had this on the tissue (pic below).

My little girl will be 3 in November, we haven’t been trying but we’ve had sex twice just before ovulation and after.

I’ve had low back pain on and off weeing a lot and few head ache and light cramping, I’ve also had a lot of bloating feeling and gas! Tested last Sunday with a Tesco pregnancy test and showed positive, tested twice in the week and all come back negative? Have no idea what’s going on! Will wait and test again Sunday! Any ideas girls??