weaning again!!!

Hi girls.. have been weaning my 20week old for few weeks now.. as was going well ( i think) but it just seems that since starting my lo crys or should i say screams every night following her bath.. it's almost like turning on and off a light.. she just suddenly starts and then after 1/2 hr -1hr she suddenly stops.. i dont know what to do.. she does seem or sound likes she is in pain?.. any ideas?? x