In reply to kgosicat:
Is the pain at the bottom of the big toe by the main joint? Does it come on when you do a lot of climbing on small edges? If so could be something similar to what I had a few years back, which was caused by me having flat feet and wearing climbing shoes which were too soft for me. Think mine was an early stage of Hallux Rigidus of the big toe, which causes a lack of flexibility and pain in the joint.
Took about a year before it got back to normal, after 1-2 months rest and not climbing much (avoiding slabs and long routes for a while), but still bothers me from time to time. A climbing physio in London (Cristiano Costa) gave me some exercises involving foot raises on towels to sort it, would recommend seeing him. I do a set of exercises every day and other things to strengthen the feet and flexibility in the toes, and lots of massaging around the big toe joint after climbing, which has made the pain gradually lessen. Try taking ibuprofen in the first few months, if the pain is still there, but don’t rely on it for long. Would also recommend wearing stiffer, less downturned shoes when climbing until the pain goes away and flexibility/strength improves.