You guessed right!

these panels really generate so much heat...?

Yes, they do...
While solar panels do generate heat, it's a normal and manageable phenomenon.

Proper installation, thermal management, and roofing materials all help to minimize the risks associated with heat generation. Most of these panels comes with heatsink which helps in cooling the heat. However, this can't be effective 100%..., there would still be a little amount of heat...,but that's not a big deal.

You won't feel it inside the house..., I felt it while installing because I was too close to the panels.