I tried running stair-sprints for the first time a couple months ago, i was in the same boat. I felt like i was going to die, it took almost two hours of inactivity before i felt normal.
5 x 500m sprint then 20 Burpees. I was suprised becuase it doesnt sound that hard , but going all out on the first sprint makes the rest of it a nightmare. The last set of burpees literally had burps thoughout it.
(running around the block is 500m rather than the 400m that is suggested)