Evertime i stand or walk my head feels heavy or tight i have acid reflux not a smoker or anything im very scared im 20 yo is it brain tumor !

Brain tumors are rar: It is easy to sort this out. Go see a doctor who may have to run a test on your brain to assure you that all is well. Brain tumors typically cause severe headaches which often come in he morning...Waking one from sleep. A ct scan of the brain can check it out if you want absolute certainty right away.

Unlikely : It could be something as simple as dehydration or anemia. See your local medical professional for further evaluation.