Chemical pregnancy explanation?

Could someone please explain chemical pregnancies for me, as i think i may have just had one?

Af was 10 days late which is strange for me. I had spotting 5 days before af was due for about 3 days, and a vvvf positive 5 days after she was due. Had heavy spotting again yesterday and af arrived today. Tested again to be sure but was bfn. Af is very heavy, and very red and clotted (i feel like thats tmi but i guess the facts help?)

Also, will this effect ttc at all? And what, if anything, should i do now? Do i need to see a doctor or am i ok to carry on as normal? Any tips for getting pregnant this month??

Massive thank you in advance lovelies xx