Well, let us try to answer that immortal question.
First let me explain what are these injections that you have to take. In this world, these are so many germs that cause so many diseases.
Why, don't you remember that bout of jaundice that your sister had last year and that terrible typhoid which your mom got. Now, do you want to suffer like them ? I am sure, you don't want to. Here is where injections come into play. These injections, also called vaccines (pronounced as wack-seens) are shots that prevent you from getting these deadly diseases. There are various vaccines available which you start taking right from the time that you are born till about 5 years and then at 10 years of age.
Then, your next question is : -
Why doesn't my mom have to take injections?
That is because, you are still young and your body cannot fight all the germs that invade it. Hence, you have to take the injections to protect your body. Your mom is now protected from most of these germs, but she may also have to take shots like hepatitis B, chickenpox if she has never got these diseases before. So go ahead, and tell your mom about it and make sure that she takes her shots too if they are required.
Now-a-day, with thinner needles available, these injections are not as painful as before. Infact, most of the times, you will not even realize when the injection has been given as you are still busy howling. Sometimes, injections may cause a little pain and applying ice on the skin will decrease it. If the pain is more, then your doctor will give you some medicine for it.
There are several drugs that can be given as injections too. However, they are not given routinely.
So, next time, when you go to the doctor-ask "Does my mom need an injection ?"