I wonder if the clucking was some sort of cough? The heavy breathing would lead me to believe it may be some sort of respiratory problem. Seeing a vet is a good idea.

When my Bam choked on a pellet he made clucking sounds, in fact he sounded like a duck. I did the bunny Heimlich which must’ve dislodged the pellet. If your bun is still breathing funny, have her seen by a vet. Aspirating (breathing in) food can lead to obstructive/ foreign body aspiration pneumonia.

Also scatter her food in the future. Some bunnies have a tendency to eat faster than is good for them, and they need slowing down by having their food scattered. It’s a more natural way of feeding as well, in nature rabbits don’t get their food in bowls =)