I'm sure Chewie will be fine; I wouldn't classify this as an attack, even - dogs are gifted with a full mouth of very effective weapons, so if he'd actually attacked him, there would be a lot more than just noise. It sounds like the other dog was trying to chase Chewie off, and using language within the normal range to do so. It doesn't make it any less frightening for you, of course, and for Chewie, too, if it was a surprise to him - and if, being on lead he felt trapped.
My main advice is to try not to let it affect you - sometimes easier said than done, I know! - and be very careful about the things you do when faced with other dogs if you are finding yourself a bit worried. It's natural for us to start tensing up, shortening leads etc when we've had a bit of a fright like this, and that can actually make things worse for your dog. Hopefully by now you've both just shaken it off, but if you do find yourself getting a bit anxious, try not to do anything that will translate to Chewie - so keep the leash nice and loose, talk to him in a normal tone of voice (or not, if you wouldn't normally) and try to behave as if nothing is out of the ordinary.