it's probably a bone spur. waiting is not a problem. get an xray and see if that's the case. the tedons that course the top of your foot may be irritated from the spur and be causing the ache you are experiencing.
That is a very common area to have a bone spur (exostosis). Typically these are genetic or from some type of traumatic event, doesn't have to be major trauma, even tight shoes can cause this.
Conservatively you may try wearing shoes that are wide and do not put pressure on the area. If you wear shoes w/laces, relace the shoe so the laces go straight up the sides and do not criss cross over this area. You may want to buy some large felt pads w/a hole in them, put the hole directly over the painful area to offload this and reduce pressure.
Ultimately, if nothing conservatively helps, you may need this surgically removed.
If the lump feels softer than bone,it may be a soft tissue tumor, typically benign like a lipoma or ganglion. Recommended treatment would be same as above.
Try to see a podiatrist in a timely fashion if possible.
Hope this helps.
Bryant Tarr D.P.M.