Physical Fitness Exercise Programs

I am a 34 year old man. I am 5′8" and weigh 154 pounds. Over the past two years, have lost almost 50 pounds by exercising and only eating 1500-1700 calories a day. I phased the program in slowly over time. However, lately I have noticed I get sort of light headed when I stand up quickly. Could this be related to my weight loss?

that’s normal. it happens to everybody.
and what’s the rush!? take it easy when standing up!
and drink lots of water… that could be signs of dehydration too.