Sighting of Summer 1975 in Longview, Texas

In the summer of 1975 was returning from a double date from taking one of my friends home; we had to cross the Sabine River Bridge to go towards taking myself home; as we were crossing the bridge I glanced down at the river and there hovering over the top of the river was a disc shaped object; it was spinning at a very fast rate and I could see green-bluish light coming from it as it turned around and around. We decided we would try to get a closer look at it by going down a side road; the next thing I remember is driving down Eastman Road at about 75mph and this thing passed us up; followed us all the way from the river to the deadend street where I now live. It5 went out into the sky hovering  over the field. I ran inside and got my mother to come out to see it and she said "there is nothing there but a star". It had stopped spinning when she came out but all of a sudden took off at an angle at a rapid rate and shot across the sky. We ran inside to call the airport to see if anything strange showed up on radar; they did not believe us when we told them what we had seen; thought we had been drinking or something. There was no sound coming from the craft at all but had a haze about it; looked like somekind of sparks coming from the water with the craft hovering over it.
Date is approximate.  PD