33 weeks pregnant, constant contractions - are they a problem?

I'm 33 weeks pregnant with my second and I've been having contractions every day for the last few weeks. They're painful and strong and will keep coming unless I lie down and relax.

I know they're Braxton hicks, but they feel very strong and I keep getting them. I didn't have this with my first.I was sitting at work today and I started getting a strong contraction every 3 minutes. My OB said to take 2 cups of water, a Tylenol and lie down. It took me some time to get home, so the contractions kept going, but as soon as I had the water and was in bed they stopped.

Is this going to be happening for until 40 weeks? Should I be worried at all?