ear trouble

Hi, I'm 32 weeks tomorrow and every time I move my head I get a pulsating in one of my ears. I get it when walking up and down stairs but sometimes just from sitting up in bed and sometimes from just turning my head. Sometimes is stays there all the time and I can't get rid of it and sometimes if I move my head a different way it goes off. It's really annoying and also starting to scare me a bit as I've had it for a while now and it seems to be getting louder/more intense and happening more frequently. Has anyone else has this? Will it go once my baby is here?