It’s amazing how much a win of some kind can improve your moral. Maybe its a PR, maybe its losing more weight than you expected that week, it could even be someone noticing the changes in your body/life and mentioning it. The important thing is to ride the emotional wave that creates for as long as possible.
There is nothing wrong with feeling good about our accomplishments. Just like we shouldn’t feel guilty for being down when things don’t go as good. It really sucks to go out for a 10 mile run and have to turn back at mile 3 because you feel like crap and you know it just isn’t going to happen or you feel the start of an injury. You don’t have to pretend that doesn’t bother you, but at the same time you can’t let the hard times set you back. Push on and see if you can fix the issue for next time.
It’s really important in running (and life) to learn from your losses and from your wins. You can’t learn humility if you never lose and you can’t learn joy if you never win.
This article describes a nearly perfect win situation for a runner.