Hi Heidi,
'ONLY' 1 stone in 5 weeks. Blimey - that's brilliant. Everyone here loses at different rates. Some have very fast losses (particularly the men) but others have much slower losses. Some lose fast at the beginning then slow down, others the other way round. However if you stick to it, you will lose.
I would try to follow the plan to the full although there is no doubt that because SW isn't a precise science there is a danger that if you try and tweak it that eventually you get further and further away from it's intended. However if you're losing at a good rate (which you ARE) then that's the main thing.
Good luck and well done so far.
Gail x