Just wanted an opinion

So I had a really crappy day yesterday. I was cramping, crying, headaching. I knew my period was due basically any second. I have the iud so I get little to no flow at all of my period. I was using the bathroom and I felt a contraction right at my vaginal opening. This was right after I finished urinating. I look down there’s a small drop of blood. Do you ladies think this was my period? Has this happened to anyone else?