圧倒される

too much for me to

It's too much for me to take in.

私が理解するには多すぎます

having a hard time

I'm having a hard time taking it all in.

全てを理解するのに苦労しています    have a hard time ; 苦労する

I can handle

This is more than I can handle.

私が処理できることを超えています

beyond me

This is beyond me.

これは私の理解を超えています

I thought I was good at math, but this, this is beyond me. It looks like hieroglyphics.

hieroglyphics   /,haɪərə'glɪfɪks/　n)象形文字