Toddler driving me crazy

I feel like my son has been driving me up the walls lately.

Just more whiny than normal and acting more bratty. I know they’re still so young but I feel like just out of no where, I get so much more annoyed with him due to him just being so bratty.

Also he’s struggling to get to sleep with naps when he usually goes down within 5 minutes.

Could this be the 18 month regression?

There doesn’t seem to be any teeth coming in at the moment either. Molars are all in but canines don’t seem to be coming in so I’m not sure if teething has anything to do with it.

I am also 24 weeks pregnant, could this have anything to do with it too?