I don't think you had enough wind. Which is a smart move to start with when you don't know what your'e doing. I had the exact same experience when I got back into kiting last weekend.
It's been three some years since I gave up on kiting and started windsurfing. I was never good, took some lessons and could self launch/land. I decided to get a big kite for the low-wind days a few weeks ago. Last weekend I went out and played around before the wind picked up to try and remember everything.
Trying to launch below 8mph, the kite will not have enough shape and the rear lines will seem WAY TOO LONG. That is exactly what I had noticed when I tried to launch by myself. I even tried adding more air to the kite with not much affect. You need wind to push the kite open before the rear lines will shorten as the kite opens.
I launched and landed once the wind picked up. Worked on my body drags up and down wind and then tried to get on the board a few times. Saw a squall coming through so I packed up and hauled ass. Though I waited for it to pass and hoped there would be more wind for me to break out my windsurf gear. To no effect of course, which is why I got the big kite.