Boy, until this latest flight, this one handled great compared to the first one I got which crashed into my pickup 8 days ago. Landings were very smooth, etc. Nice. I took it up for some late day photos since a large ship was passing through the open bridge near our house and all seemed fine until I decided to land. The only thing different about this flight is that at some point I realized I had accidentally bumped the switch into Smart mode and obstacle avoidance on but I put it into Angle mode turned off obstacle avoidance. I don't remember if that was shortly after take-off or what at this point, but it was not near the time when I was landing. Everything seemed normal until maybe 30' above ground and the H did not want to come down any more! If I let go of the control stick, it went higher. Weird. I haven't looked at the handy dandy card yet with all of the colors on it but the big rear light in the rear was flashing purple and white (bluish white to me). I moved it from 25' away from me (facing away) to about 40' away and tried landing again and it did not want to come down! I was thinking of getting DC on the phone to figure out what the heck to do but figured I did not need anymore distractions and just needed to keep trying. I just held the throttle stick all the way down and it came down very slowly although it also seemed to want to drift away towards a tree in front of it. I wish now that I had turned the video on. Finally I made contact with ground with the landing gear but it wanted to tip over on me like my first unit. I just held it stead and pressed the power button and shut down the motors. I believe the taillight also flashed red then also. I have no idea what had just happened. I had something like 19 satellites in coverage. I'm figuring I'll at least do another compass calibration again before flying. THOUGHTS????