Does having flat feet mess with your spine?

Indirectly: Depending on how your body compensates for it, flat feet can range in severity and flexibility. You're joints and posture can compensate bio mechanically as you take a stride and indirectly, your spine is affected. At your age, if you have no pain, there's little to worry about.

Maybe Orthotics.: It sounds like you may have a biomechanical instability in your feet that is passing problems "up the kinetic chain." custom made prescription orthotics, made by a certified lab, under the recommendations of a podiatrist can help tremendously!

Sure can: Flat feet not only effects the feet but ankles knees, hips and lower back. Your house has a foundation and if its off so is the house. The feet are the foundation of the body. Custom orthotics should be a big help!