My 7-year old has bumps on booth foot bone (looks like first metatarsal, at the top) and it hurts when we lace up shoes too tight. what could it be?

Depends: If the bump is hard usually is a deformity of the underlying bone. If it is soft it may represent a cyst like a ganglion. Since it is on both sides it probably is a congenital anomaly. See an orthopedic surgeon or podiatrist for an evaluation.

See Podiatrist: He could have a foot deformity that is causing elevation of the bone, or could be very flatfooted causing protrusion of the bone. Need an exam and x-ray.