I am 25 and have a vp shunt due to a tbi when 19. do i need to be worried about exercising, as well as fluctuations in blood pressure?

No: There should be no general life / function limitations or restrictions.

Shunt Activities: People with hydrocephalus (improper drainage of cerebrospinal fluid (csf)) have shunts placed to divert CSF from the brain to other areas of the body for absorption. A properly functioning shunt allows people with hydrocephalus to perform many activities. Contact sports that may damage the shunt should be avoided. Blood pressure control is important for all people.

You should be OK: Generally, people who are otherwise healthy can lead normal lives with a vp shunt. The one caveat with exercising is to avoid contact sports where you may hit your head. The reason is that with a head injury there is a chance of a hemorrhage such as a subdural hematoma (sdh). If this develops, the shunt will potentiate its growth as it will allow the CSF to be "squeezed" out and the sdh to grow.

No high impact: Regular exercise beneficial, high impact sports not recommended.