I'm 31 wks today, and been getting lots of BH contractions for past 3-4 days. At least, I think that's what it is - bump goes tight and hard, and I can usually feel baby kicking with it. I know BH are normal, but I swear it must be 20-25 times a day. I'm lying in bed now and it's been constant for 15 minutes or so. Is this normal?