It's likely a node issue at the time.
It could be something peakd related.
It happened to me a couple weeks ago.

Your rep score is useless, I wouldn't worry too much about it.
It only measures how much stake has voted for/against you.
Variations in its display are, again, likely node related.

You've been here long enough to start looking around, give ecency.com and hive.blog a look over.
Maybe they do things better for you.
They are skins for the game.
They work with keychain, too.