Any chance?

My cycles are all messed up from Provera. 12-15 was my actual cycle than I got positive OPKs after, than 22-25 was heavy, thick brown spotting. I’ve been nauseous as heck, my breasts are so sore and I’ve had cramping here and there. I took a test Saturday afternoon from Walmart and it was negative.. is there still a chance I could be pregnant?