I'd agree with the others. It's probably not contractions but I'd just check with your doctor to make sure. That's what they're for!
It could be trapped gas or constipation... Ive had that sharp pain that wudnt go away on the left side also. It was painful to the point I couldnt walk properly. My last pregnancy I had the same worry as you, thought I was having contractions but then realised it was trapped gas which is very common during pregnancy.
Could be round ligament pain I'm a ftm at 22 weeks I had experienced it when I hit 22 weeks my birth education teacher said that it was round ligament where your ligaments stretch but it hurts because your ligaments are not stretchable
I'd go to the doctors.. as I had this with my son & I found out I had a uti that had lead to a kidney infection.
But it could also be the stretching of your ligaments which is also painful!
Hope This helped & hope it stops soon♡