It now sounds like you've got some debris in the needle valve. Pull the needle assembly, remove the needle valve and look through it and I bet you see a piece of something in there. Clean it out reassemble and you should be able to properly tune the engine.

Or... if you had a rough landing... hold the plane nose up, and shake it up and down a couple of times. The clunk could have gone to the front of the tank, kinking the fuel line.

Somewhere you have a fuel flow problem.