The problem is that you arrived in Beijing very late the day before. I guess you didn't get up so early in the morning, so don't go to Gongwangfu. It's very late in the afternoon after seeing the Forbidden City and Beihai Park, unless you plan to have a quick look inside Gongwangfu. I suggest you go directly to Wangfujing.
the next day
Both the Great Wall and the Ming Tombs want to see it. I suggest you go to the Beijing Tourism Distribution Center in the southwest corner of Tiananmen Square to sign up for a one-day tour. 150 yuan. It's too late to go if you're not familiar with yourself. Come back at 5 pm and take the subway directly to the Bird's Nest and the Water Cube.
The third day is fine. Anyway, these places are together