Have you gone to the doctor yet? I've already told you that herpes doesn't cause sores IN the mouth, but on the lips.
This has been going on for almost a month, right? The only way to know what is going on is to see a doctor.
Herpes doesn't cause blood blisters, irritated tastebuds, ingrown hairs, etc.
Stop popping things, and see a doctor.
I realize you are 16 and going to the doctor without your parents finding out is daunting.
If you are in the US, you can get checked and treated for STDs without your parents permission in most states, and they can't tell your parents in most states. To find out the laws in your state, call your local Planned Parenthood.
You are assuming your gf has herpes. Has she ever tested? Ever had a cold sore? Maybe both of you can go to Planned Parenthood together.