Scattered throughout the dream there are things that point to something in your life you feel the need to get rid of.
Killing and toilets, are symbols of needing to 'kill off' parts of you that you find distasteful(Bad habits, negative thoughts etc).
Toilets represent actions or emotions you see as wasteful.
Being in a posh building, and floating are symbols of needing to better yourself, and rising above current situations.
The bridge is a representation of a transition( from one way of life to another).
A train is the need to do things in an orderly, or structured manner. It could also suggest you feel as though you are stuck in a rut, or just going along with everyone else.
You being a little white ball is odd. People rarely see themselves as an 'inanimate object'. It may be that you feel small, that others don't see you as capable of doing what you set out to do. Being white suggests purity and honesty. That you (as a ball) have spidermans' powers, suggests that you will do whatever you need to, to get where you need to go.
Fire could represent strong emotions and fiery tempers. But it could also represent a cleansing, or a renewal of some sort.
Your old school is representative of simple, more carefree times.
Your mom is a symbol of guidance and nurturing, maturity and respect. That she says she's Audrey Hepburn may signify that you need to acknowledge her and what she has done for you. Because she shrinks and gets small suggests you feel your roles may have been 'reversed'. That you may need to take care of her in some way. And because you get angry with others who speak ill of her, suggests you are wanting to protect her from something.
Taking to the cute guy, and he says he just wants to get back to work is your subconscious telling you that you may need to take something more seriously.
His typing fast may be a suggestion that there is something you feel you are capable of doing without much effort. That you have the skills you need to 'get the job done'.
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Is your job causing anxiety, or fear of failure?
Is there some area of your life that is wasteful?
Do you feel you need to get rid of, or end something...bad habits, bad relationship, etc.?
Has your mom been helpful to you, but you feel guilty about it, or forgot to acknowledge her efforts?
Do you want or need more structure in your life?
Have you be 'going with the flow' but would like to 'break free' and blaze your own trail?
Has anyone been treating you as though you are small and insignificant?

Hope this give some insight, Good Luck!