Am I allowed to give myself an IV (details inside)?

The last couple of visits to the ER all that happened is that I take a bed and they let me go after getting an IV of water… Wouldn’t it be simple that before I get sick that I drink some clean water hours before I feel ill… Or have my own IV (maybe take a class on giving myself an IV and saving the time and the trouble of taking care of me). I hear that doctors give themselves IV’s when stressed out, could the class where the doctor learned that be taught in a first aid class?