I started my first batch of beer, a "Nut Brown Ale", 2 weeks ago. Its initial gravity was 1.040. As per the instructions, I siphoned the beer into the secondary fermenter (a glass carboy) after two days. The airlock had already quit bubbling in the initial fermenter. Its gravity was 1.020 at that point. Today, 10 days after the move to the secondary fermenter, I tested the gravity and it was only at 1.018. The directions on the kit said it should be around 1.008-1.012 after 7 days.
It built and maintained positive pressure on the airlock the entire time since I moved it to 2nd fermenter, but I never actually saw bubbles. My room temperature is around 65F at night to 80F in the days. The beer tastes like "beer", but is kind of weak.
What did I do wrong? Should I add more yeast?
Update: I did the swirling method a few days ago. The airlock has started to show activity and a layer of bubbles has formed at the top.