Most likely a fuel issue (but not necessarily), but probably a dirt issue because the problem happened so suddenly.

Dirt in the carberator fuel screen "should" accumulate gradually, so a lean condition would come on gradually as well.
With so sudden of a problem, I'd just go ahead and pull the carb and disassemble, clean, and reassemble. Likely a piece of something in the needle opening itself.

Also check your gaskets and diaphragm for integrity. Air leaks would cause the same symptom, and about as quickly.

Bottom line; the problem is somewhere in the carb.