A lot of "shoulds" are leanweighing on my back(mind | head | shoulders).

I understand it's time to move my lazy butt and complete all theseis stuff but I can't because I'm way too lazy.

残念！

Recently, I have been slacking recently.

A lot of "should"s are leaning on my back.

I understand it's time to move my lazy butt and complete all these stufftasks but I can't because I'm way too lazy.

Recently, I have been slacking.

Or you could say 'slacking off.'

And I should also finish reading some books.

A lot of "shoulds" are leaning onagainst my back.

Although not really grammatically correct in majority of sentences, Americans add 's' to things like: shoulds, coulds, buts, etc. when talking about a lot of those things as a noun.