Quick Fermenation?

I brewed an Irish Red this past Friday. Gravity was 1.052 Friday night around the same time I pitched the yeast. I only made about 3 gallons but I still pitched the whole vile of Wyeast Irish Ale Yeast. There was noticeable fermentation by Saturday afternoon but by Sunday it had slowed dramatically or stopped altogether. I transferred to secondary on Tuesday afternoon, at which time I had a gravity reading of 1.020. Today, Wednesday, there is no noticeable activity (air lock). Should I wait a week or so before bottling or is the fermentation done?

Yep...just because there is reduced airlock activity and the grav is at 1.020 it doesn't mean the yeast job is finished, they like to clean up after themselves if we let them. That's why many of us leave our beers in primary for 3-4 weeks then bottle. We have found that it makes for clearer, cleaner tasting beer.