If you had false labor, were the contractions you felt then regular? How long did they last before going away?

I've been contracting pretty much every 8-9 minutes for the past 3 hours, and I'm beginning to wonder what is going on. Sometimes, they space out to 12 minutes or so, and sometimes they come a little closer together. They feel like a combination of pressure and period cramps. I took some Tylenol and a hot shower about half an hour ago, and they've spaced out a bit. They're painful, though, and some feel like period cramps.

I know that if this is real labor, they'll get stronger. But if it's false labor, is it going to stop, or am I stuck feeling this way until the real deal? I'm 37 weeks today.