Is my dad blackmailing me?

I am 12 years old, and my parents are not divorced yet, but they are separated. They pretty much have joint custody of me. My dad took away my iPod, my desktop computer, and my cellphone. I decided I would go with my mother. He gave me a 2 week punishment (overkill...) My father decided that if I did not go back with him, I would not be able to get my privileges back while waiting the two weeks at my moms (he told me my punishment stops and I can have my privileges at my moms) Is this blackmail or just plain bitterness?