Hi UG, I'm new here so I'm not sure if this belongs here, but I'll leave my question anyway.
Basically I've been screaming since 2012, but the honest truth is, I have no idea whether I'm doing it right or not. The thing that's bothering me is, that I can only seem to scream low, never high. Apparently it should be the other way around, or so I've heard. I don't even have to cup or anything, and I can scream low notes easily. But if I even to scream high, my throat starts hurting. It feels scratchy and a little sore, but it's only a mild pain, nothing severe feeling. I can always talk just fine afterwards with no difficulty.
I'll use Bring Me the Horizon's Pray for Plagues as a reference to what I've been screaming to lately. I can scream the lows with no problem, but not Syke's highs. I can try screaming those for a little, but it starts to get on the painful side. Maybe I'm using different techniques for both without knowing it? I just want to be able to scream higher notes, is all. Or to know if I'm even doing it right, based on what I have said.

I've been trying this for 2 years now, so I'm not sure. It seems like I have an idea of what I'm doing, but there are times where it hurts because of the highs that make me reconsider that.
Does anyone have an explanation? I'd really appreciate any help here!
And my apologies for the lengthy post.
If you are experiencing pain you are doing it wrong and could be causing damage. Get with a vocal coach who understands rock music and they willl teach you how to do it without hurting yourself. My friend Pete Strobl does this on the west coast for many pro vocalists.
"Your sound is in your hands as much as anything. It's the way you pick, and the way you hold the guitar, more than it is the amp or the guitar you use." -- Stevie Ray Vaughan

"Anybody can play. The note is only 20 percent. The attitude of the motherfucker who plays it is 80 percent." -- Miles Davis

Guthrie on tone: https://www.youtube.com/watch?v=zmohdG9lLqY
I had to look up the band you mentioned. From what I saw, he's not so much of a traditional screamer as he is a rasp singer. This takes a lot of proper practice, starting with diaphragmatic support, proper cord closure as well as making use of soft palate vibration.

In other words, get a teacher. Or learn to scream in a more traditional fashion and then use that to do what you want. We can help with that in the screaming/growling sticky.

Get me a clip of you singing something and we can go from there if you don't have the cash for a professional trainer.