If you have a headache when you finish diving or your jaw just hurts from grinding your teeth from the excitement, you probably need a new mouthpiece. After getting certified, I complained that my head was hurting after each dive. People told me I was ascending too fast (which I could have been), but I didn't think that was it, my ascents generally take me 10 minutes or more. After doing some research online, a lot of people had this problem and they resolved it by replacing their mouthpiece, mostly with a Seacure.
My first replacement Seacure was the Seacure Type II to go on my Oceanic Alpha 8 (great reg) and eliminated my headaches and jaw fatigue immediately.
First off, when you receive your mouthpiece, before it's even put on your reg, you will boil some water, turn off the heat and dip the mouthpiece into the water for 10 or so seconds. Then, put it directly into your mouth, creating a mold of your teeth. You would be sure not to bite down too hard, as biting hard will make too big of an indention and will cause your airway to not be as open (please learn from my mistake). Then using the included ziptie, attach it to your reg.
I will make a recommendation, go with the BLUE! After 30 or so dives with my clear mouthpiece, it started to get the same discoloration that a clear mask gets. Brownish green in color. I have yet to put my blue one on my setup, but after speaking to Seacure, it doesn't change colors like the clear.
If you decide to get a Seacure, be sure to get the right type, there are 3. Most sites that sell them have a type list with the reg types it fits, so be sure to read it.
