You're either overtrained which can cause you to become listless, or you've been taking too many hard shots to the head.

If this is from taking a lot of punches, I recommend backing off on sparring for at least week to allow yourself some recovery. In the meantime work on honing your defense with the question in mind, "Why am I getting hit?" Take this thinking to the bags and while you're shadowboxing. If you're getting hit consistently with a particular punch, keep it in mind and work on the defense against it. The same applies to any tendencies that cause you to eat punches.