Mental block against math as a grad student

I’m doing a master’s in mathematics full-time after working as a software engineer for eight years.

I really enjoyed it at first, but I started to experience a “mental block” against math now that we’ve started doing some more difficult work.

I’m finding it difficult to get myself to study or concentrate. My brain fees like it’s protesting when I consider studying.

Anyone else experience this before?

I thought I had a passion for maths, but it’s hard to get myself actually do the work.

Is it supposed to feel easier or more enjoyable?