I've had a large bunion on my right foot for years due to wrestling. Recently it has become extremely painful to touch or pressure. Any ideas why?

Bunion pain. Bunions can suddenly start hurting for many reasons. Sometimes the nerves that run along that area to supply the toe are bruised, irritated, or otherwise injured because they've been stretched across that "bump". It could also be bursitis, when the fluid filled sack that lubricates tendons becomes inflamed. Could also be ligament pain because the ligament has been stretched...
Bunion. Bunions are degenerative in nature they only get worse with time and will cause arthritis in your big toe joint if it interferes with your life visit a podiatrist and there are many simple procedures to correct the deformity.