Congested baby!

My son has been really congested and has a wet cough since he was 5 weeks old! He's now 9 1/2 weeks and he's still like this. The doctor told me his lungs are clear, and it's not the flu or anything else that's serious which is all good but then why is he still like this?? He has a hard time breathing when he gets all clogged up and I'm doing saline spray and trying to get as much of that crap out of his body as I can which makes him scream his head off anytime I suck the stuff outta his nose:/ I feel like he's so miserable and I just feel helpless. It freaks him out when he's super clogged and can barely breathe I can tell he panics sometimes... I just need some advice on what to do?! The doctor hasn't given me any medicine or anything