My Dad locks me in my room, is this right?

me and my dad dont have the greatest relationship. we argue a lot, I often go out with my friends in the evenings to parites etc and get in around 12/1am. This makes my dad mad as my curfew is 10pm (I'm 15... this is ridiculously early) so I end up grounded which means I sneak out and it pisses my dad off even more if he catches me coming back in. He's recently started locking me in my room when I got to bed so I cant sneak out. After 9pm I'm locked in my room. I personally think this is ridiculous and all it has achieved is making me very very mad at him. If him and my mum go out for an evening, to make sure I stay home he locks me in my room when he leaves at say 6 or 7 pm. Its stupid. He treats me like a fricking animal, locking me away in my room unless I am permitted to leave. Also if him and mum go out in the morning he often doesnt unlock my room before he goes out so im still stuck in it until sometimes 9 or 10 o clock in the morning. I dont like being caged in by own father. Do you think this is right? I have an en-suit thank god! But what if theres a fire huh ?!!