I have a few tannish, roundish spots developing on my belly. Anything to worry about. 29 yr old male, otherwise healthy.?

You are likely fine. It is not possible to tell you with 100% certainty but what you are describing doesn't sound suspicious. However, you should have these skin lesions evaluated by a dermatologist.
Difficult to say. . Dermatological issues are very difficult to assess without an examination since skin issues need to be physically seen. Follow up with your family doctor or dermatologist for a definitive diagnosis.