Cervical changes- 30 weeks!

I'll be 30 weeks in 2 days. This is child number two. Doc checked my length today and says I'm dial aged a finger tip. (Not a big deal being this is baby number two.) He also says my cervix is already thinning and softened a good bit. I have tons of Braxton hicks contractions all of the time and spiratic real contractions depending on my days. Any feed back?? He has limited my activity some what, limited me picking up my toddler (35lbs), and says I need to rest more. I'm also supposed to limit sex and no semen.