In my unqualified opinion, you need to take immediate remedial action and this means more than going to an optician.
If the eye has become sub-standard, there is a reason and you need to know what is causing the problem. Just blurry, is not an option for a pilot.
There may be several reasons why the cornea, lens and or its encapsulation become unclear.
Local hospitals in the UK will usually have an emergency clinic with an eye surgeon in attendance. His staff will put you through a full check up before you go in to see him or her.
Astigmatism is in simple terms a variation of focus with angle. Any correction has to be made at a specific angle but the lens can be clear in other respects. However, the image even with moderate astigmatism, can be very unclear. Red LEDs on a clock for instance, can show a secondary image to one side, leaving the top an bottom well defined. Or any other angle of course.
Keep us posted.