Flints come in all sorts of shapes and sizes, and humans just can't help but attach significance to some of these shapes. They often get it wrong; we can get led astray our experience and intuition, and hope!
Your specimens are indeed flint, most probably Cretaceous in age. In principle, since dinosaurs were around at the time, fossils of dino teeth could be made of flint. But that would be very unusual. From the way flint forms, the only type of flint teeth would be casts (where the original tooth left a cavity that was later filled with a pre-flint silica). That is unlikely partly because of the environment: flints form in chalk, and the warm shallow seas where chalk forms are not the sort of places dinosaurs would hang out - there would be little suitable food there.