Welcome Bets, nice to meet you.
It sounds like it could be MS, but there are worse things. It can take awile to get a DX, like everyone says, there are lots of Mimic illnesses that must be eliminated.

I was DXed in 1976, after having an, "I can't walk", episode. I did have case of double vision/ON, sometime after being DXed. Many do start their MS journey with Optic Neuritis, with a DX from their Opthomoligist.

I'm surprised your Optho didn't suspected MS.

It's great to have you with us here..