Regular pain in toe. Visit for this.

My two year old son often complain about pain in right toe or near about it happens every 2 or 4 nights since he was about 6 or 8 months old. In the day light he has never complained about the pain but while going to sleep it starts and he wakes up in the night with high pain that he cries for 30 minutes due to pain holding his toe. We try to rub or massage but it never helps we have start giving ibugesic for pain relief so it reduce the pain. We have asked this to many doctors in regular visit but all never took it seriously as if it is unknown to them some said vitamin deficiency some said growing pain and some said physiological but no medicine. I am very much worried that it turn to a very serious problem if not identify also don't know which kind of specialist i should visit for this.