HELP PLEASE!

So I'm 28 weeks pregnant and have just recently started feeling pressure very low (feels like she's in my vagina!) and I feel light flutters like her hands are pressing against me. I thought I was crazy because I didn't think she could flip or be so low this early, anyway I went to the doctor yesterday and they checked my cervix and she reached in and said "Oh ya there's her head!" WAIT WHAT?! Now I'm told to do limited standing/walking no bending stretching or picking things up. And have to wear a belly band everyday to keep the pressure up. I'm so worried about early labor 😩 has anyone been through this? Also, will having sex affect this even more? I should have asked when I was there but I had so much going through my head! My SO thinks we should take a break from it.