Mountain bike fit is a bit different than road fit.

If you mainly ride on roads a road or cyclocross bike is a probably a better choice in the long run than a mountain bike. A used road bike is a good way to start while you figure out what you really want. It may be camera angle but that frame looks small to me. You can always change stems and handlebars to change reach and height of the handlebars,

If you ride regularly and it doesn't feel right, then it isn't right.