(OP) If he cut the sutures rather than tore them out, she should be able to tell that. As for putting his fingers in his wounds... if he did additional damage, she may be able to tell that it isn't something that would just be caused by moving wrong/over-exertion/etc., but I doubt she could specifically tell that it was self-inflicted as opposed to the result of a lucky hit.
Re: PSA: Wound care - Also can do some medical Q&A
Otherwise, it'd be his horrible lying skills. :)