Is this a DIY fix or a pro job?

Usually fine to DIY

Small, shallow dings that haven't broken through to the foam -- surface scratches and dings in the top coat -- are the classic candidates for a repair kit and an afternoon. If the foam isn't exposed and there's no soft or spongy spot, the risk of getting it wrong is low.

Get it looked at by a shop

Cracks that run in a line rather than a point, any spot where the foam is visibly exposed, delamination (the skin separating from the foam, often showing as a bubble or a dull patch), a buckled or creased deck, and any damage near a fin box or leash plug are all worth a professional opinion. These usually involve structural strength, not just cosmetics.

A board with exposed or waterlogged foam shouldn't keep getting ridden in that state -- water soaked into the foam adds weight and can spread the damage well beyond the original spot. If you can't get it repaired right away, at least keep it dry and out of the water until you can.