@MissMushy I couldn't agree more with what @burvantill and @Heather-Boyd said.
The same happened to me last year. I was very dissatisfied with my job and was planning to quit, which I eventually did, but I was so stressed while going through that experience that the sole idea of putting pen to paper was freaking me out. Every sketch felt like one of the 12 labors of Hercules.
So I am going to join them in saying: take it easy (also, these ARE super challenging times and nobody has the compass, so I think it's ok to feel a little lost and have to figure it out along the way), find something extra-small that brings you joy (who knows? maybe you don't need to sketch at all and you can just grab a bunch of crayons and express your feelings the Kandinsky way) and I am sure that all your creative powers will gradually awaken