Smoke smell question. Is this normal?

[Ilovemyyaris]

Okay hi everyone. I've got a 2011 yaris with less than 20,000 miles and I've noticed recently on the highway if I go more than about 80 mph I notice a smoke smell.

It happened first when I passed someone on a road. I thought maybe it was the other car, but then it happened again and now any time the engine is rev-ing a lot.

I took it to the dealer and told them about it when I got my oil changed but they didn't seem to concerned. They said they looked at it and they didn't see anything wrong.
It drives perfectly normal for the most part I think. I don't notice anything much out of the ordinary.

I never notice seeing any smoke, just smelling it through the air vents when the air or fan is on. I always have it set to circulate, I never have it set to outside air.

Only other weird smell I've noticed is that sometimes it smells moldy but I heard that was normal it's just mildew from the water from the air conditioner.

But this smoke smell has me worried. I have a theory that maybe it's just at high rpm the engine gets a little hot and the mold or whatever burns or something but I wouldn't think that to be the case.

I guess while I'm at it I might as well tell about the small thing when driving.
Sometimes if I'm going fast, but have to slow down really fast and then take off again there seems to be hesitation for about 1 or 2 seconds then a sudden jolt off. Not sure if that's normal or not. This is the first car I've actually owned so Idk if I'm just being paranoid or not.