21 weeks and a lot of Braxton Hicks

I’ve been getting them since 17 weeks and they’re causing me so much anxiety. They’re not very strong and don’t last long but they happen pretty frequently. I try to stay hydrated, pee if I have to, change my position sit/lay/stand/walk whatever I’m not doing when they start... my doctor said to call if I get more than 4 an hour but I’ll get like 4 and then I can usually stop them by taking a shower or having my husband rub my back to help me relax so I’ve never called about them. They’re just really annoying and upset me. I’m not sure what else to try

Also this is my second baby. With my first I didn’t notice this happening until around 37 weeks and when I was in labor with her my contractions were every 2-3 minutes apart for over 24 hours before I even started dilating..