Pain on top of foot

Can anyone help? I hurt my foot over 3 weeks ago. It wasn't any particular incident - I just took my shoes off one day and the top of my foot was sore. It's the high point (the spur) between the big toe and the ankle. I spoke to my physio (having physio for another problem) and she said it's probably tendonitus. I have re-laced my trainers to avoid fastening them over the 'spur'. Today I tried running (haven't run for 1 week) and padded my foot around the spur to try to alleviate any pressure on the foot. I did 5 miles but it was getting very uncomfortable towards the end. Has anyone had this before and how long can I expect it to keep me out of running. I'm getting really frustrated!!!