Confused

So had a loss a couple of months ago blighted ovium. Than I had a regular period thinking ok now my cycle is back. Today I’m 4 days late and negative pregnancy test but the last month I tested opk almost everyday no positive not even close and I took one today and it’s positive 🤨. I’m assuming maybe cycle still out of whack from the loss? I thought for sure my period would be coming with the negative test sore boobs alittle moody etc. Any thoughts? I do know a previous pregnancy took till 21 days to show up but that one didn’t work out so well either😔 definitely frustrated