I am also thinking that the membrane may have gotten inflammed or irritated somehow.
This could take a little while to heal up. Just keep flushing the eye out for awhile to help.
You could consider getting some antibiotic eye ointment also, just for some extra help with
any bacteria that could be built up or causing irritation.
****** prestonphelps******
It would be easier to start your own thread so we don't hijack the OP's thread.
That way we can review your tank setup, etc to be sure everything is all good.
There are several reasons for irritated eyes, such as improper lighting, substrate, etc.