That doesn't sound particularly expensive to me. A glass of decent white wine in my Sunday evening boozer (Greene King) typically costs around £5.50. I often drink one of their premium lagers at around £4.50 per pint, so that would be a tenner for the two (which isn't that much cheaper than the £11 you paid).
More usually though I drink the bottled Camden Pale at £4.40 for 330ml, which is equivalent to £7.57 per pint. However if I drink it in a London pub it's usually £6.20 for a bottle, equivalent to £10.67 per pint. (So you were getting a pint of beer AND a glass of wine for roughly what I pay for a pint of beer in London).
If I drink in a wine bar (or a decent pub, with the sort of wine which nobody should ever put soda in) I expect to pay between £20 and £25 for their cheapest bottles of wine.