Mountain horned lizard

Question
Good morning Tracie.  I bought a mountain horned lizard a couple of weeks ago from a local pet store.  He has been eating fine and stools look well.  I noticed a couple of days ago however, that he has a bump about midway down his back and near the top of back.  It is a tad smaller than a pea at this point.  This evening when I returned from work I noticed him sleeping in his water dish and yesterday he spent the night on the ground as well.  His coloration however is green with yellow highlights.  I'd imagine this is a good sign as most lizards I've had before that can change color have more vibrant colors when they are doing well, though this fella has changed colors a lot since I had him, which is actually very cool.  I just want to make sure that this is not something that could be a serious health issue.  There also seems to be a similar swollen spot near the base of his tail on the left side.

Answer
Hello Matt,

Do you happen to have any pictures of those bumps?
It is probably metabolic bone issues I would think unless they are cysts or abscesses from previous injuries.  
Are you using a UVB light & giving him calcium also?
How old is he?  
If he does have calcium trouble, it is from poor care that was from his previous home.  It takes awhile usually to set in.  
Has he eaten anything since you got him?
What are your temperatures in the tank, he needs them around 85-90 for basking & 78-82 or so on the cool end with 70% or so humidity.

Do you happen to know if he was wild caught, or no?

Tracie