Fenix 5 battery life questions

I've had my Fenix 5 for a few years now and the battery is starting to feel less than it used to be. Of course this is expected with age. Is it reasonable that I'm using about 80-85% of my battery over a week's time with always on heart rate, always connected to my phone and roughly 3.5 hours of running with gps+glonass?

Also I noticed that this morning when I finished my run it said I had 20% battery but sometime between then and now it has gone up to 22%. What is going on with that?