I was laying down watching airplanes fly by my window. I saw one fly by, then shortly afterwards something else flew by. It looked like another airplane at first, but it was dark and I could only see the lights. Their were three lights, two white in the front one red in the back. They made a triangular shape two in front, one in back. Before it left view of my window, it quickly and abruptly turned around and flew in the other direction. The turn was not something a plane could do that quickly and easily. Then it immediately plunged downwards. at this point it became one solid red light, then started strobing white light. Then all the lights went out and there was nom more sign of it. The whole time I felt a sense of shock, awe, terror, and danger. Then it left and i felt fine. Also the entire time I saw it I heard a low, deep, humming.At exactly 5:15 PM CET on the same day, with the exact same conditions and descriptions, I saw the same craft, fly by then stop. It stayed their for 10 seconds then then the lights went out and that was the last I saw of it.