middle of my right foot hurts when I walk?!

the most likely cause of you pain is planar faciatis. This is cause by numerous possible things but based on your recent activity of taking up jogging its most likelty caused by the over expanding of your arch because the support in your sneaker is inadequate for your arch height. Some simple ways to make this pain go away are to use insoles in your shoes which have stronger arch support. Depending on where you live if you go to a running speciality store, or make a single appointment with a physical therapist they will be able to analyze the height and depth of your arch and recommend you a good insole

push up on the spot just behind the ball of the foot. If it is a fallen metatarsal arch, you need to make a small lump that pushes up there, and either build it into the shoe, an insert, or easiest, just tape it to the bottom of your foot to support that arch.

After about age 30, if you gain weight your arch in the foot gets strained. The best thing to do is not walk on hard floors, buy new atheltic shoes that are comfy, and take about 1200 mg of ibuprofen 3 times a day until the symptoms subside.

get some roomy shoes.