Really there isn’t enough information to tell, how deep did you go or was 20 feet the max? How about previous dive profiles, depths, total time, how long had youbeen at that depth, etc. Any dives after? Based on what you describe however, it is possible you got a type I hit, which is pain only and focused in the joints. Even with the other detatils filled in that is the most likely probability even though 20 feet wouldn’t be enough to do it on one dive alone. I suspect there is something more to that day that one dive. Best Wishes and Godd Diving Carmine DMT-A Dive Medical Technician Note: the previous is not a diagnosis and should not be construed as such. Any dive that causes pain or discomfort unusual to a diver in the first 24 hours after diving should be considered suspect and the diagnosis of a diving illness/injury professional should be sought immediately. The best source is DAN, (Diver’s Alert Network) 1-919-684-8111 or 1-919-684-4DAN (4326)