My first boy I lost was from the exact same description I think you describe, but it's not gone critical yet unlike his, but you have a small window to treat it so ya I would get to your vet asap when you can. This video I have is the sounds my boy made when he was critical and lathergic:
[Plz note, this might be stressful to watch for some viewers, this is just to help those who fear their pet rats may have Phenomina or advanced URI as my previous boy did. If you listen closely he makes loud clicking heavy breathing sounds, his fur isn't groomed, he's very dehydrated because he's completely given up on drinking and eating despite me syringe feeding, and his male parts issue was due to complete dehydration...was a very sad time for all of us to see him deteriorate like that, for me and everyone here at Rat Shack. I hope this vid can be used to help point out these illnesses for other rat owners so they may avoid the same out come]
[BBvideo 425,350:2z8r062k]http://www.youtube.com/watch?v=FzD6EOMKkGQ[/BBvideo:2z8r062k]
That was sadly the night I had to put him down, because after everything I tried to do, including giving him Nebulization Therapy plus doxy, and syringe feeding him to keep him hydrated, he was just too far gone. The faster you treat this the likely they can recover, and would highly recommend baytril, doxy, and Nebulization therapy to aggressively treat it as well if you can afford it or if your vet suggests it as well.