Pain base 5th metatarsal

Hi

In September I was on holidays and I banged the outside of my right foot on a pretty solid table. It was quite painful at the time and I remeber thinking when I did it did I break my foot. But the initial pain subsided in a few hours and I just remeber discomfort more than anything. Then on my way home whilst waiting for my flight I was walking a bit of a distance through an airport and was thinking how much my foot hurt. After arriving home and over the next 8 weeks the pain in my foot got worse to the point of severe excrusiating stabbing pains after walking on it for an hour or 2. I have had an ultrasound, x-ray and two mri's which show nothing. Im waitng to see the orthopedic doctor again to show him the results of thesecond mri but I have seen them and there is no sign of anything wron. When I went to visit the ortho for the first time he could see I was in pain and have a lump at the base of my 5th metatarsal he gave me a boot to wear. I have wore it for 4 weeks now and the pain has definitley reduced 30 to 40%. It has cost me nearly $1000 to get this far only to be none the wiser. Has anyone else had this experience or have any insight to share, I would really appreciate it.
Thanks