HELP!! Dog is drooling excessively?!?

I have a french bulldog (1 y/o) who drools only on his walks or around other dogs. However, I noticed he is excessively drooling (not in puddles but he has salvia hanging from his mouth) which is unusual for him. He is also farting more than usual for a frenchie. Additionally, he lets out what sounds like a cough every now and then. He seems to be acting normal but he is usually a lazy sleepy dog anyhow. I'm really worried and my dog is basically my world!