I have dizziness whenever I stand from sitting or just rapid change of height in general, also I have fatigue with the dizziness. my blood pressure however is normal.
Does anyon know why this could be??

I am not a doctor, but it sounds like it might be anemia, or low iron in the blood. The only way to know for sure is to make an appointment.

Not enough information in your post to give a relevant and meaningful answer.

What do you mean by "dizziness?"
How long does it last?…secs, minutes, hours?
Do you vomit with the dizziness?
are you on any medication? e.g blood pressure tablets.
Any problems with your hearing during an attack?
Any fullness in the ears during an attack?

As you appreciate. these questions need answering.