I Have Pain In The Right Foot That Occurs When

I have pain in the right foot that occurs when walking or standing with my weight toward the front of the foot.The pain is severe and occurred 2 days ago when I got up and felt a severe pain. I cannot make this pain occur by bending my foot with my hands, pushing on areas of the foot. It does not occur if I place my heel down first, but only when the weight is on the front of the foot. It is not swollen. I am 82 years old and this pain has not happened before. I exercise 7 days a week, incl. 2 days at a hospital facility. The equipment includes an exercise bicycle, a tread mill and a new step machine. any comments. YYYY@YYYY