Ttc help

Hey all im 28 and trying to get pregnant with no luck at all my periods gone from 28 day to 26 now 25 day but this month im a week late but after having sex friday i did start spotting brifht red then stopped then the same on Sunday after sex then nothing did s pregnancy test nothing im lost and feel alone but i know im not im not stressed just not sure whats goin on iv had 8 miscarriages and have 4 children to previous relationship