My boyfriend is very sick, any ideas of what this might be?

He became very ill last night, his chest hurting especially when he talked along with his throat and head and coughing up brownish phlegm. Today he only worsened, his fever reaching a high of 103.4 tonight, but after Tylenol it lowered to 101.something. He couldn't even get up this morning without almost falling but he did manage to get up to take a shower later on this afternoon. His mom plans on taking him to the ER tomorrow morning when she gets home from work, and I'm going to call him a few times tonight so he can take his temp to monitor it, but I just wanted to know if anyone had a clue what this might be just to calm my nerves a bit. Thanks.