Some blitz games are well worth analysing. If you are losing in openings that you plan to play in serious tournaments, it's a good idea to analyse what's going wrong.
Also, if you lose to a specific tactic, it's a good idea to study the tactic and make sure it doesn't happen again.
So yes, analyse some blitz games. But if you're just goofing off and dropping pieces, it may be better to spend your time analysing classic games instead.
As a general rule, don't analyse a blitz game for more time than it took to play it.
I play a terrible blitz game. I'm noticeably much better just playing a regular game that is expected to last at least 45 minutes. I analyze my long games and I sometimes actually learn something new that helps my playing improve. Would analyzing blitz games help me get better at blitz or probably not? The reason that I'm asking is because I really enjoy playing fast chess with a time limit.