I suggest that you take 2 days off, see what happens. if the problem is still there, rest more until you feel like riding again. meanwhile change the angle of your bars, raise them a little bit (so there's less pressure on your hands while riding), try riding with no gloves, change the hand position more frequently. Exercises for hands are essential when bike-touring, because you don't move them that much while riding. If the problem still exists cancel your trip and go see a doctor.