Display item fiasco

Anglaise_2

I just wanted a few opinions on this, and some advice as to whether or not there's anything I can do about it now.

I was shopping in New Look the other day, going through the summer sales and I spotted a nice skirt in the "Under £10" section. I tried it on, thinking I'd bagged a bargain, but then I realized there was no price tag on it, plus the size label had been ripped out.
Several shop clerks investigated it, as the skirt could not be found on file and eventually someone ended up going to the manager. It turned out that the skirt had just come off a mannequin, however the manager had said that it should be sold at full price (£19.99) as there was nothing wrong with it.
I tried to haggle with the shop clerk, insisting that it was a display item and should not be sold at full price, asking her innocently to just knock a few quid off. This whole thing lasted for almost half an hour, and I ended up paying full price with just my student discount taken off, which I felt was totally unfair.
Is there anything I can do about this now? Anyone I can talk to about maybe getting a part refund?

Looksguywalker

No, you should have just refused to buy it and walked away.

Enterprise_1701C

The shop don't actually have to sell you anything. If you did not think it was worth the price asked then you did not have to pay it.