Hi, thank you for asking Healthcare Magic. With this presentation, I think it is necessary to rule out any possible blood shortage (anemia). Standing up abruptly can cause dizziness and lightheadedness through a physiological (normal) mechanism. Having only these may not mean that there is a problem but adding tiredness to it means that there could be a problem. I would suggest you see a General Practitioner for proper assessment and management. I hope that answers your query. If you have additional questions or follow up queries then please do not hesitate in writing to us. We will be delighted to answer more questions from you. I wish you good health