are these pregnancy symptoms?

Evelyn • wife since 2017 and mom of a beautiful two year old boy and baby girl on the way! Both my rainbow babies 🌈

I miscarried january 14 I was just a few days pregnant so my hcg levels went back to zero un just 3 days... I've been really worried tho, since last week Ive been having a lot of nausea and sometimes vomit, horrible cramps everytime I stand up it hurts so bad!! I started having unprotected sex once the bleeding stoped, what do you guys think its happening???