I got Nelson from a family friend nearly a year ago. I have no idea what a normal tortoise looks like ahah! He's 3 years old, about 6" long. Pictures below
He looks healthy to me try giving him different types of food but be careful because they can only have certain types of Lettuce.. I have 2 Russians myself [SMILING FACE WITH SMILING EYES] their my babies
Get him a cuttle bone and some direct sunlight and he will be healthier. He may be suffering from a lack of UV needed to process the calcium into strong bones. The diet will need to be much more varied.
The members here will be happy to help you improve your torts lifestyle and health. A picture of your enclosure and a picture of the torts tail will help ID the maturity and sex of your tort.