I’m scared righty is drying up

Julianne

My babe is about 4 months now. Recently my LO hasn’t been nursing on my right side as well. She goes for like 4 min and then pops off and starts crying. She’ll shake her head on the nipple and cry until I put her on the left. I noticed it’s a lot smaller than before also. Anyone else have a similar situation? How should I increase my supply? I was going to pump just on that side every other hour.