Congrats on your first finished brew! Now take what you have learned and brew another, better, batch.
You can definitely reuse dry yeast, but do be aware that the packets are not TOTALLY free of bacteria. These packets are fairly cheap compared to liquid yeast and you will get better results by pitching a fresh packet each time. If you are going to use the yeast within a couple days then you should have no problems with the best case scenario being you repitch at bottling time into another batch immediately. Any longer than 1 wk and I would probably get another fresh pack of yeast. Just my 2 cents.
Once again, congrats on the pale ale and enjoy the fruits of your labor. Meanwhile, brew up another batch so you always have some ready to drink!
Cheers -
Brewinhard