I'm assuimg your temp is in Celsius but to be sure...Celsius or Ferenheit?
20 degrees C = 68 degrees F.
(sorry, that's for my reference as I haven't converted my brain to Metric...yet)
Here's a link that I pulled off a Google search.
It says 48 - 59 degrees F so 9 to 14 degrees C for fermenting so you might have fermented too warm for the style but as long as it finished fermenting...
The other members would have a much better understanding of what effects the warmer fermenting temp would have on the brew but here's my understanding...a lot of brutal off flavors and aromas. Hopefully not too much that it went arseways and is all gammy
As far as conditioning goes there are a LOT of threads from very experienced brewers but I'll reiterate what I've learned. 3 weeks @ 70 degrees F or 21 degrees C. 3 WEEKS!
You do that you'll be good to go
I think I got that right....