If the bugs you saw are blk and very tiny look like pepper then she has mites, better get her treated asap.. they will make her anemic and the rest of you flock needs to be treated as well. Not saying this is whats causing her feet problem, don't know about that. also you'll need to take out all bedding and treat entire coop, then just put in enough bedding for the week because you'll need to retreat again.. All the best.