Ttc after miscarriage and now spotting

Cassity • Laila 05/15/17, Xander 4/10/18, and Grace 11/06/2019
I has my miscarriage 5 weeks ago and I have yet to get my period. I've been having very very very light cramps and about five minutes ago I went to go pee and I saw spotting. I'm not sure if it's because maybe my period is coming or if it's implantation bleeding. Anyone know when I should test?