Lower back pain

I've been doing so well since surgery on the 7th...but in the past few days I've had severe lower back pain on my left side. I don't know what it could be. It stays for awhile and then it's gone. It hasn't happened enough to figure out what causes it yet, but wanted to see what thoughts you all had!

Have you been sitting, standing, lying down in a different position than normal, maybe due to stomach pain or soreness?

When you say severe, though, how bad is that?  Like on a scale of 1 to 10?  Are you having any other symptoms?  If it's really severe, I wonder if it might be a kidney stone?

I had some pretty bad lower back/side pain the first couple of months after surgery. Especially when driving or sitting at my desk. I could tell it was muscle pain and not something wrong inside (although I sometimes worried). It eventually eased up and then went away totally. I honestly think it was lack of muscle tone and weight shifting. My muscles weren't used to holding up my body in a sitting position because it could always just lean on the fat rolls to stay upright...really! I have heard of others who experience sore muscles as their weight shifts and they have to adjust to their new bodies.

I wasn't doing anything in particular. It came on so I had my daughter rub my back..then all of a sudden I felt nauseated so went to the bathroom and gagged a few times(sorry for the TMI) and it hurt for about a half hour more and then it was gone.  Last time it happened I went to sleep and it was gone when I woke up!