I am sorry to hear about your situation. You have sufferred from one ailment after the other and your body is weak. The diarrhoea has probably left you dehydrated and with your electrolyte levels disturbed. Since you mention that you have developed hemorrhoids, the blood loss from the same is further going to increase your weakness. Since you are ill, your appetite has come down and since you are not eating well, the complication further increases. The combination of all these factors is responsible for your feeling weak. Things you can do are- 1. Take protein rich diet. Our body is made of proteins and you need it for its repair. Meat, eggs and fish contain proteins and need to be taken in bulk. 2. Take more fluids. Take juicy fruits including citrus fruits. 3. Take curd or yogurt in more amount. I hope that with proper rest and diet you would gradually be fine.