You don't need to act like a dick (as you put it) All you need to do is attend the office, request the money that you are owed and wait there... even if it takes all day... Trust me, I've done this... even to the point that they rang the police because I refused to leave until I'd been paid what was owed to me.
The police woman arrived, asked me what the issue was, I told her she asked them why I hadn't been given my money, which made them step back a bit, they thought that the Police would just turn up and turf me out

- She told them that I'm not causing any obstruction but if I was still here at closing time to contact her again and she'd come over to help with the situation.
Come 6.00pm I was still sat there waiting for my money, she dutifully turned up and told the receptionist that unless they were refusing to pay me there wasn't much that I could do, she replied with and I quote...
"he's a big un, we were afraid to speak to him, we don't even know how much he wants!"
The police woman looked at me, back at her, then laughed... and said that she was now obstructing and lying to a police officer, if she wishes to make a complaint about me then please do so, but considering I had told her in front of the receptionist how much I was owed she can stop messing about give me my cheque and I'l be off.
10 minutes later, cheque with two signatures in my hand I happy.