You added yeast to the boil?
I've heard of that being done with old yeast as a nutrient but your not going to get proper fermentation (or any fermentation for that matter) by boiling the yeast. Please elaborate.
After some thought I'm going to assume you meant to say dry extract
, in which case all is well. If so, you did what is referred to as a late extract addition. Not really necessary in a stout, but shouldn't affect fermentation at all. Again, some elaboration would be helpful.