It's happened to a couple of women I've been with - and one of them was squirting during our time together, so lack of wetness wouldn't seem to be the (primary) issue. In both cases, though, the condom I was wearing wrinkled up on me because, after going at it pretty hard for a while, I was no longer 'rock hard', something that happens to a lot of guys when wearing a helmet. The moral of the story is, if after a few minutes you're no longer the 'Man of Steel', don't force the issue. Pull out and get it hard again, playing with her while you do to maintain her wetness, then go back for another round of fun.
imo, if she's starting to dry, its perhaps time to mix it up and use your face for a few minutes. she'll moisten right up.
never blood, just ripped the condom off my shit before...good thing I was still very in control but still was spooky