I think that the most likely explanation is that you are feeling a bump where two of the bones of the skull join together under the eye socket. These two bones are the zygomatic bone and the maxillary bone, which come together and fuse in a suture that can often be felt just in the center line of the eye socket on the upper ridge of the cheek. This suture can be fairly prominent along the upper edge, and if you are feeling carefully along the ridge below the eye socket you may feel it. This finding is completely normal and is nothing you would need to worry
On the other hand, if the bump you are describing is actually visible under the skin without touching it, or if it is mobile under the skin, then this could be a small cyst. Again, cysts are generally benign and you would not need to worry about a cyst unless it became very large, at which point it might be uncomfortable or might be a cosmetic problem.
Cysts that become large can be removed surgically, and you should talk to your primary care doctor
about this. They can confirm whether or not this is a cyst and whether or not you should do anything about it.