One common cause of pain in the arch of the foot is plantar fasciitis, which refers to an inflammatory process affecting the band of ligament-like fibers that runs through the bottom of the foot. This plantar fascia is often stressed with repetitive motions that stretch the fibers, such as with running, jumping or dancing. Patients with plantar fasciitis often complain of pain when the toes are pulled upward with one hand and the other hand pushes on the bottom of the foot in certain locations. Often, conservative management with ice, pain control with non-steroidal anti-inflammatory medications (e.g. Ibuprofen) or Tylenol, rest, and more effective arch support with new shoes or inserts results in improvement of symptoms.
Since you don't remember a specific incident in which you injured your foot, the chance of a broken bone as the source of your discomfort is less likely. However, you could still have suffered a small hairline fracture
in one of the bones in the mid-foot. If your pain does not improve with conservative management, then having it evaluated by your primary care physician
would be the next step. He or she can order some plain x-rays to help rule out a small fracture.