SORRY vs EXCUSE ME vs PARDON

Trying to clarify in this post different expressions used to apologize with some examples:

Excuse me and pardon me are polite expressions that you use when you do something that could be slightly embarrassing or rude.

You usually use sorry to apologize after you have done something wrong.

According to Macmillan Dictionary,excuse me is used fo:

1. politely getting someone's attention
2. showing you are sorry for interrupting someone
3. asking someone to move so that you can get past them
4. politely telling someone you are leaving

Sorry is used for : 

1. emphasizing how bad,stupid,or embarrassing something is
2. feeling sadness or sympathy because something bad has happened to them
3. disappointed about a situation,and wishing you could change it

1. We usually say excuse me before we interrupt or disturb somebody;
we say sorry after we disturb or trouble somebody.

Compare:

• Excuse me, could I get past?… Oh, sorry, did I step on your foot?
• Excuse me, could you tell me the way to the station?

I beg your pardon is a more formal way of saying sorry.

• I beg your pardon. I’m afraid I didn’t realize this was your

2. If we do not hear or understand what people say, we usually say Sorry?What? (informal) or (I beg your) pardon?
Americans also say Pardon me?

• “Mike’s on the phone.” ” Sorry?” I said “Mike’s on the phone”
• “See you tomorrow”. “What?” I said “See you tomorrow”.
• “You’re going deaf”.” I beg your pardon?”