What is the difference between "What should I do", what am I going to do" and "What will I do"?
If I am asking myself what should I do in a specific situation which one of those 3 above should I use?
What is the difference between "What should I do", what am I going to do" and "What will I do"?
If I am asking myself what should I do in a specific situation which one of those 3 above should I use?
This is asking "what is the correct or best thing to do?". It doesn't say anything about what actually will happen, just asks what would be the right thing in this situation (but it often implies that once you figure out the right thing, you will probably also then go ahead and do it):
I want to go to my friend's party, but I also told my other friend I would help them move. What should I do?
This is asking "what options do I have for things I can do?", or "what would be the least-bad thing to do?". It implies that you may be unsure whether there actually even is a good way out of this situation. Because of this, it is often said with a sense of anxiety or despair.
I don't have enough money for rent, and if I don't pay it tomorrow I'll be evicted! What will I do?
This is often used when you don't have a fixed set of options to choose from, or a particular problem you're trying to solve, but you are just wondering what the next thing you will decide to do will be. It is also sometimes used in a bad situation to mean basically the same thing as "what will I do?"
Let's see, what am I going to do today?
"What should I do?" - Asking someone "what do you think is the best thing for me to do?"
"What am I going to do?" - Asking yourself what to do. Usually not a real question, but a way of expressing that you're upset about an impossible situation. For example, "If I run, the wolves will eat me. If I don't run, the zombies will eat me. What am I going to do?"
"What will I do?" - Not very common, but often the same as "what am I going to do?"
Can also be used to restate the question "what will you do?" like this:
"The zombies are at your door! What will you do?" "What will I do? I have no idea!"