Can Braxton Hicks be close together? Should I be concerned?

I’m having painful contraction-like pain in my uturus. Only been happening for maybe 15 minutes now but every couple minutes lasting two minutes. Afterwards I’m getting cold chills. It’s my second pregnancy and I’m 30 weeks. Is this normal? I didnt have any early contractions with my first so I have no idea what I should be looking for or when to be concerned enough to get checked out. I’m also having weird pulsing in my vagina but that doesn’t hurt at all.