RGP lenses making vision worse?

I've started wearing RGP lenses in the last few weeks after having CXL in my right eye about a year ago. The lenses were fantastic at first and gave me almost perfectly clear vision in both eyes. However about a week and a half ago I noticed my left eye was starting to become blurrier, whether I had my contacts in or out, or if I was wearing my glasses. I haven't worn my lenses for almost a week and my left eye is still blurry.

I do have keratoconus in my left eye but didn't have CXL on it as my consultant told me it was stable. When I last saw my optometrist a few weeks ago they noted that the lenses were too tight and they ordered some looser ones. Now my vision seems to have got significantly worse in that eye in the space of a few days, and I'm really worried that the lenses have effectively permanently changed the shape of my eye. Is that something that's possible?

If this is permanent it's not the end of the world as I can just get a new prescription, but I'll be really frustrated as I had only just got a new prescription for my glasses, and ordered new prescription sunglasses etc.