Have you ever seen ghost like this?

It happened with me when i was in first year of Engineering. I & my friend used to go tution which was by 5:30 morning. I always used to go my friend’s home to call him. One day i went to call my friend as usual. We were just about to leave, only that time his mother said ” Do not forget to tap off the water tap” Everday we used to tapping off the water tap which was in the parking area. We just went to the parking area. It was very dark as usual. We stepped down two steps of the last stair case & what we saw was a white amoebic shaped image just coming near to us.
We moved back i.e. at starting point of same stair case.The image disappeared. Again, we stepped down 3 to 4 steps, same image but this time size was bigger than prvious. We thought someone would be kidding with us. We saw back that anyone focusing battery light but, no one was there. The image was looking like shining glitters in the water. We ran away & thereafter didn’t dare to go again to “Turn off the water tap”. We could not sleep two days. I think it’s not an illusion.