Here's something I just recently thought of doing. Make a playlist on your ipod or mp3 player, but only put songs that make you extremely happy and want to dance without caring. Set your alarm clock to wake you up with this list. Go to this play-list whenever someone makes you feel incompetent, and know that they are wrong.
Only YOU can let someone make you feel that way. And only you can push yourself into a better mood.
Whenever my boyfriend or I are starting out the day in a cranky mood, we usually text each other saying the day is going to be great, awesome, amazing, fabulous. Whatever perky and over the top adjective we can come up with, we use. I'm not sure about him, but it usually makes me smile when he tells me "Today is going to be so awesome that you'll be throwing up awesomeness all over."