Husband had vascetomy but I think I'm pregnant


So a year ago after our 2nd child was born my husband had a vasectomy. I was breastfeeding so period didnt return until 10months pp. My youngest is 16months old. Past 2 or 3 months my periods have been wild they were normal when period came back. I'll have spotting, periods and it seemed and on every other week. So I took.a test like a month.ago, looked positive so I took another one looked postive again couple days later I take another negative. Thought well maybe I'm just go crazy. Well the next day I woke with morning sickness still negative. Next day period came. And my hubs never went and got tested after the procedure. So we aren't even sure if it was successful and he says they've been hurting like a sharp poking feeling.

Well this month after my period after those odd test, 12 days after period i.had 2 days of brown light spotting enough I had to wear a panty liner. And period should be coming soon. But I've had cramping ever since the spotting, backache, slight nausea, and some major dizziness lately.. I tested 2 days ago and I got one super faint "postive " but it was one I wasnt sure about.. but I'm just wondering if yall have stories about vascetomys failing and surprise babies. Or just any insight why I might be having all this werid stuff going on with my body.