Right rib/pain,dizziness I’d call ASAP as it could be a start of preeclampsia and needs to be monitored to keep momma and baby safe. Also could be baby lying on blood vessels which in turn could cause dizziness and light feet,try to keep off the back,short periods of time are ok but the right and back laying for long periods are not recommended.

You should probably call your doctor asap or have someone take you to the hospital.