My brown ale smelt somewhat like beer and possibly vinegar and tasted the same but with a very subtle sweetness but also very dry and puckering.
I used only used dry extract and boiled the hops, no grains.
What was the OG reading? What was the FG reading?
If these measurements are within the expected boundaries of your yeast strain and fermentation has stopped, then it is probably not infected. Remember, green (un-aged), un-carbonated beer will taste a bit different than the finished product. Dumping a batch should be the last resort.
Your issue sounds like what I just dealt with. Mine was due to an Acetobacter infection. Acetobacter can be caused by many things, mine was probably in part due to poor cooling after boiling. Two batches completely ruined. Some people have let their beer sit and age to see if it works out, I dumped mine. If you use plastics and have ever cleaned with any abrasive material, a scratch that you don't see could be the culprit. PBW and Star San are great, but you can be sidelined by materials like plastics. I'm slowly switching to glass. Google Acetobacter. Good reading.
"Acetobacter produces acetic acid instead of lactic acid. Acetic acid is the major component in vinegar so it if you have a strong vinegar flavor in your beer it is very likely due to Acetobacter. Interestingly, acetobacter requires both the bacterial infection to occur and also requires oxygen to grow. So in addition to having poor sanitation, you would need to have oxygen present in the beer, either by infecting the wort before fermentation has taken place or by aerating the beer during fermentation or transfer. So if you get a vinegar tasting beer, you need to check both your sanitation procedures and also be careful not to add air to your beer once fermentation has started."
I've had two beers in about 100 sour on me (that weren't intended; I've also done several intentionally soured beers). It's a bummer, but not something I would throw out. Especially if it's a lemon-vinegar sour; it can be refreshing. They usually take a bit longer to bottle carbonate.
Clean after use, sanitize before use and this shouldn't happen, but dust from milling grains, bacteria in lines and even just exposure to air can all cause this.
I find souring a beer intentionally frighteningly simple...
I don't do it, but several homebrewing allies "push" all their beer (rather than using autosiphons) with CO2 so they can minimize the wort/beer contact with air. I suspect this would help as well, but just practicing good sanitation should go a long way.