I asked my doctor about this, because my knee will crackle loud enough that you can hear it sometimes! He said it was the cartilage wearing thin, and was a natural part of aging. Basically, as long as it doesn't hurt, it's not something to worry about.
But in your case, you're reporting pain. This isn't normal, and you should talk to your doctor about it to determine the cause.
Writer, mother, wife, and breadwinner. I love to run, but running doesn't love me, so I'm switching to my low-impact bike.
I'm not pregnant, just fat: My blog. fatnotpregnant.blogspot.com/
| current weight: 190.6