Wouldn't call it typical.
I had an iPhone 5 for a while. I could easily get through a day and have some left over. I'd guess it was around 5 hours of usage time and I'd plug it in around midnight and take it off at 7:30 or so when I got up.
My brother has one of our spare iPhone 5's now and I replaced the battery with a new one. I haven't had any complaints.
I would suggest a full restore to 8.2 and don't restore from a backup since it can bring the issue right back with it. Install just the apps you need and go a couple days. I'd imagine the usage and standby will go back to normal.
A battery replacement might be needed too. The one I sold went back to Apple for the sleep/wake button recall, and they gave it a new battery while they were at it. So do check your serial for the sleep/wake button recall or battery recall.
I went two days on my 5c more than a few times too. And my 4s. So it's possible