Felix was crying to come upstairs so I let him up. A few minutes later, he got down low and started breathing weird. It's like a hiccup but he kept turning his head from side to side like he couldn't breathe and I freaked out. I tried listening to his chest and I hear crackling. Not sure if it's coming from his stomach (since he just ate) or his lungs. I went to call his vet immediately but they're closed and I don't know what to do. I don't even know what this is. I have a full day tomorrow and I'm afraid to leave him alone. He's acting normal otherwise but I don't know how long this has been going on since I just witnessed this horrible episode. He's licking his lips a lot and some water came out when he was in that position. Picture isn't Felix but that's how he crouchs down when he's breathing unusually.