Hills are always going to make you hurt. It's the nature of hills. Don't worry about your speed, because you'll always feel slow when you're chugging away. You got up the hill, didn't ya (one way or another)? There you go!

I will say that it helps me to remind myself to pedal in circles, rather than just mashing the pedals. Kind of eases up on my legs and gives me a little burst of speed when I've been just plodding along.