Possible Military High Flyers over BFS today

[Angry Turnip]

I was out in the garden today putting out some food for the birds,and keeping an eye out for any high flyer vapour trails.
At around 1330 I heard what sounded like two fast military jets heading West-I couldn`t see them nor any trail,but they sounded very different to airliners and were much louder.
Could still hear them after 5 mins approx.
 
Later at approx 1605 I heard a similar sound and saw a tiny thin single vapour trail heading from East to West,looked like it might have been an F-15 but was very high and moving fast,so this is just a guess,didn`t have my camera with me.
 
Anyone else see or hear them,or have them on radio?
Thought it may have been US aircraft from Lakenheath but again just a guess.

[Angry Turnip]

What time was the Cessna 560?
 
I`m not sure,but I thought most military stuff didnt show up on SBS.
 
The aircraft I saw at around 1600 didnt look like a civvie.
 
Thanks for the info.