Sunken eyes in any tortoise can be a sign of dehydration. I'm no expert, but I would give him/her a nice long soak. I wouldn't imagine there are any major issues. If it really bothers you, you could take him to a veterinarian to put your mind at peace. ?
Ok thanks, so I would just give him a soak every day for awhile? I never see him drink even though he has a water dish, would the soaks be enough to rehydrate him?
I do not believe that you can over-soak. You could soak every day for about 30 min. each time for a couple of days. I cannot tell what size he is from the pic, but a hatchling needs soaked daily for 30-40 minutes. If it is a sub-adult, then once every couple of days ought to do it. That is when it is completely healthy.
Are you maintaining proper humidity in his enclosure? Is his substrate slightly damp?
You can also spritz his shell with water a couple times a day. It's best if you use rain water or distilled water for this so his shell doesn't get hard water stains.