Brown spotting 19 weeks

Just noticed a tiny bit of brown spotting at 19 weeks pregnant. The weird thing is that it seems to happen every 3-4 weeks and I almost always have a dream about bleeding the night before it happens. Just yesterday, I was saying it felt like I was due for some spotting and sure enough, here it is.

I had a scan the last time it happened and everything looked good aside from a somewhat low lying placenta and a small hematoma. I feel like it’s probably cervical irritation from forceful vomiting and constipation, but don’t have confirmation.

Anyone else deal with this kind of cyclical spotting?