Hello amanda Welcome to Health Care Magic The symptoms you developed like sudden light headedness, sweating, pain in abdomen, weakness, and severe tiredness may occur due to a number of reasons in you- one thing we can think is acute attack of acidity. As you had coffee and then cigarette so it may cause increased gastric acid secretion and may cause symptoms like severe abdomen pain, restlessness, vomiting. But it don t develop suddenly. Other possibility is attack of anxiety or Panic attack. Symptoms like restlessness, shakiness, tiredness, abdominal pain, light headedness etc. may be seen. Sweating is also a presenting feature. Treatment with anti anxiety drugs like SSRI, SNRI etc. is needed. For episodic control of anxiety you can take Benzodiazepines. But visit a psychiatrist for proper evaluation. Other possibility may be attack of gastroenteritis which may cause hypotension, and vomiting. So if you develop loose motions and have more vomiting visit a physician for evaluation. Thanks Dr. Seikhoo Bishnoi