I have uneven eyes and it is very noticeable in pictures. It is not something I notice in the mirror. How could this be? (Photo)

The first three pictures are taken with a regular iPhone front camera and this is where the uneven eyes are very noticeable. The last picture is taken with Snapchat which is the same image you would see in the mirror of yourself and there it is not very noticeable if at all. I am definitely going to ask my eye doctor about this but I would like to be familiar with any possible diagnosis and or treatments.