When i stand up, i can feel a pulse in my head kinda like a wob wob wob sound. i am on hypertension medication, but is this a dangerous sign?

Maybe/maybe not: Your blood pressure rises when you stand up..this is normal. So it sounds like you are sensing a pulsation when your blood pressure rises. This probably means your medication is not perfectly controlling your blood pressure. Depending on where the "wob, wob" feels, it could be related to a bruit, or sound of blood going through a narrowed blood vessel. You need to discuss all this with your doc!