{{{{HUGS}}}} take a deep breath. You're not alone. I can't count the number of night I was where you are. It sounds like colic may have reared its ugly head.
First thing to know is that at 6 weeks its not unusual for a LO to not have a lot of activity time. For many 6 wk olds a diaper change is all the A time they can handle, so if thats all your LO can do thats ok, you can lengthen that in time.
Him being able to sleep through noise is actually a good thing in the long run so I wouldn't cut out the noise entirely.
I'm not sure if your bottle feeding or breastfeeding, but either way its possible that your LO is having gas pains and thats what keeping him up.
If you bottle fed try burping him after every ounce or two to help with gas.
If breast fed try to cut foods that might upset his tummy, like broccoli or milk.
Either way if after a few hours he's still fussing, try feeding him again, when they are fussy they burn off more calories and may need more to eat.
Now something that worked for my LO is I swaddled her, and sat in the rocking chair, I held her on her side facing me, sitting in the crock of my arm, not to close to the breast so she didn't think it was time to feed, then I rocked with her, and shushed or talked softly to her and I gave her a paci. This bothed calmed her and help relieve the gas she was having. Once she was calm I would try putting her down. Sometimes this would take an hour, but she was clm most of it and, while it was hard, it didn't last forever and she learned to sooth herself.
At this point its really about survival. Do what you need to to help your LO sleep.
HTH
