Dropping?

Ok so last night around 3am I started having dull cramping.. like I would get right before my actual period cramps would come.. I took at hot shower and went to bed... I woke up around 1 this aafternoon with very sharp pain in my lady parts. It lasts for about 1 or 2 seconds and it goes away.. about 15 mins later it comes back. If I’m sitting down I literally jump up from the pain.. I’ve been drinking ton of water and walking around to see if it goes aways.. and it doesn’t... when I’m not having those sharp pain I’m still cramping... my sil said that it sounds like he trying to drop.. is there a time limit or how long ima feel this sharp pain for? Is it contractions. I’m 38 weeks tmrw