this took place in feb 2010, some day around the 20th. i was 17 at the time. i was out one night with my (at the time) girlfriend, we were lying beside the thames when at approximately 8:30pm i saw a glowing orange, 5-point star shaped ufo spin cross the sky from the direction of the street behind us to the ne (above as we were laying down) and head over the water to the sw, passing directly overhead. i sat up to look but it was already out of sight behind the treeline across the river. the object was spinning fairly fast whilst flying in a dead straight line at high speed, i'd say it would have cleared horizon to horizon in around 10 seconds and although i cannot be sure of altitude, i would guess comfortably at around 15,000ft with perhaps 1,000ft leeway. though the sighting last just a few seconds, i believe that what happened next may be related. a few minutes later, having explained what i'd seen to my girlfriend, i began to feel uneasy; my head hurt, i kept feeling dizzy and i felt sick; i've never had a migraine but i know plenty who have and that is roughly how i imagine them though maybe it wasn't as bad since i wasn't incapacitated by it and it passed after around 10 minutes. but after that i got the most intense feeling of being watched i have ever felt, even to this day. i sat up and was looking around us, my girlfriend later said it was as if i 'knew' someone was there and was trying to spot them. i was scared, shaking, my breathing became erratic and i tensed up to the point she was unable to move my arm when she was trying to calm me down. after about half an hour, i suddenly stood up and said i was taking her home. it was only a short walk but the whole time i was tense and my arm was locked around her waist extremely protectively and i was constantly checking our surroundings. when we arrived back at her house, she insisted on calling my dad to come and get me as she was concerned for me and i couldn't stay at her's as her dad and i didn't get along. my dad met me at the end of her road, he asked what i'd been drinking or smoking. i hadn't been drinking and have never smoked or taken any other form of drugs. i relaxed as we walked home, it must have been around an hour and half from sighting to when i felt 'normal' again. the experience has stayed with me because although i was aware of my actions i wasn't in full control. not like i was being controlled, just as if i was on auto-pilot. i had never had anything like this happen before and have not since. the fear, the feeling of being watched were so intense i have nothing to compare them to.