Hi, my son has accidently knocked into my tummy rushing past me this morning. It wasn't really painful but definitely a slight blow. Baby moving as normal but I'm o negative and only had anti d injection yesterday. Do I need another? My instinct tells me no, I wasn't winded or marked and surely the 28 wk injection protects against this sort of thing? I had no anti bodies detected from my bloods earlier in the week either. X