stacksitting while using inner corset

Hi Esther, There's a warning on page 28 about herniated discs and I was diagnosed with a protruding disc at L5 S1 area so I have skipped lessons 3 and 4 and I am now learning lessons 5 and 6 but on lesson 5 you have to start by stacksitting which I skipped. Should I go back and learn lessons 3 and 4 even though I have a protruding disc? I suffered my injury in early February of this year. Thanks.