Advice about wide walking shoes - please

Hi

Since being on this diet (6-7 weeks) all ailments I was experiencing have disappeared.  I had constant sciatic pain, constant hip pain and (4-5 weeks prior to this diet) progressive knee pain - all in my right leg.  

Due to my new-found energy, I've taken to walking a lot more.  I've always walked, but I've just upped the time I spend walking.  I'm always careful about what I put on my feet and comfort is important as I have wide feet.

My problem is that, during the past 8 days, I've been experiencing pain (very sharp) on my right foot between my 3rd and 4th toes.   I've never had this before and quite miffed as to why it's happened now. 

When it's bad, the pain travels up the foot and under the outside ankle and slightly up my leg.  I've done a bit of research on this and come up with Mortons Neuroma, although, I believe this is NOT what I have as the pain I have is on the top of my foot.

I visited my podiatrist today and he says that he cannot see anything that is causing the pain (hard skin, corns .... that will explain it).  He fitted a pad so that my 3rd and 4th toes would spread when I put my foot down.  Although I've only worn scandals today, to give my foot the maximum spread, the pain is still there.

I was wondering if anyone can advise me on what this could be and which footwear would be best.  I just want to get back out there as it's frustrating to have the energy but not able to do anything with it.

Peace. x