What Causes Pain And Inflammation On Middle Toe?

My middle right toe is extremely painful and red. I am having trouble walking in any type of shoe. It has been bothering me off and on for about a month, but now is very acute. I work out at the gym and do treadmill work for 40 minutes 4-5 times per week. I also have orthotics in my new sneakers, due to a painful left foot due to a Morton's neuroma that I had removed, but i still have residual nerve pain. The right foot has been fine, but it has a matching orthotic. What should I do?