I usually pitch at 55F-60F. I use ice to keep my fermentation temperature in the low-mid 60Fs for the first 2-3 days of fermentation - that keeps ester production down. Put a t-shirt (pref dark color) over the carboy to keep light from skunking your beer. It's unlikely that you contaminated the beer as long as your sanitation practices were sound.
What's the recipe? Is this an extract kit? If it was a partial boil, the OG discrepancy could be due to poorly mixed wort+top up water (it's harder to mix it thoroughly than you'd think). Or it could be due to more boil-off than you were expecting if you're using software like Beer Smith or some online calculator or whatever, you could figure out how much water to add to get your OG down to 1.052, but most people will probably say don't mess with it at this point. Your beer will be a little bit stronger than you were expecting, not much, no big deal.