Why ask a question if you're not going to listen to the answer. Everything you've said sounds normal...

"Boost changed as soon as it got cold"
"Still boosting 12-13 in 3+"
"Can't feel a difference in power"

100% normal man

If you still don't believe it's normal do a leak test and tighten the clamps in the pic I posted.

 

no man i just seriously think i dont have enough problems in my life so this is huge for me lol