I Have Noticed A Round Ball In My Vagina Area,

I have noticed a round ball in my vagina area, it does not hurt, but seems to be noticed more if I'm on my feet all day. I can actually push it up without pain, I've had 3 children, ages 25, 14 , 9. I am 50 yrs. old. It seems to become more present during the end of the day. Once I have gotten off my feet, or wake up it is not there, I can feel it weighing down and protruding. It is round and smooth. Any suggestions?