Is it bad that an 18 year old has carpal tunnel already?

Can be fixed: Do not worry, as we see carpal tunnel frequently as a consequence of keyboarding on computers, i-pads, cell phones, and sports. Not a sign of impending disease and easily reversible. Get it fixed and resume your activities.

No not bad but: Certainly make sure diagnosis is correct and there are not issues such as diabetes thyroid disassembly or other endocrine issues or metabolic problems.