Should i be worried about losing 9 pounds in 4 days? am i about to have a heart attack?

Weight loss: Loss of weight that fast likely has a large element of fluid loss. It doesn't necessarily imply a heart attack coming but isn't necessarily a good thing unless the reason is a fluid overload is being reversed rapidly.

Not likely: Rapid weight loss can be due to multiple causes. What other symptoms are you having? Loss of appetite, vomiting, diarrhea, etc can all be implicated. There needs to be more information to give a better answer for direction.