I have almost all of the song Laundromat by rory Gallagher ( live in europe album) learned. The part that stumps me is the part at the end when he plays the riff in a major key.

The song is in Am, so when i play Amaj it sounds awful. can anyone tell me what exactly is going on here and how to understand it?
Doesn't sound like the song in a minor key to me
Fender Classic Player 60s Strat
Washburn HB35
PRS Santana SE
Yamaha Pacifica 112MX
Vox AD30VT
Fender Champion 600
Dunlop wah
Danelectro Cool Cat fuzz
Am, D, G...Loks minor to me. I can also play most of it note for note using Am Blues, unless its F Sharp maj, but i dont think so.

Il question my guitar teacher...