First job anxiety: normal?

Hello all: I am a brand new, fresh-out-of-grad-school TT prof in the humanities at a SLAC (graduated in May, started the new position earlier this month). I completely understand that in many ways I have won the job market lottery— I am in a place I love, getting to do a job I have always dreamed of doing.

Despite all this, I am filled with a sense of dread. The first week of classes has made this worse, to the point where I have been asking my partner if I maybe made a mistake in devoting my life (and my 20s-30s) to pursuing a career like this. I came home from teaching my first two classes and felt like I was the world’s biggest phony.

I think (hope?) it should level out and I should be fine by like month two, but did others experience this level of stress and uncertainty in their immediate post-grad positions? I am not new to teaching, my grad program had me working as a TA the entire time, so I think this must be anxiety about the big change and the transition from teaching assistant to instructor of record. Maybe not looking for advice but commiseration: is this normal? Am I just overthinking the stress of a new job and obligations? Is this feeling of inadequacy going to go away?