According to Digiguide, Five does indeed have coverage (highlights of Sunday's games, followed by a live game) on Monday night (or rather Tuesday morning).
As for the other options, keep an eye on Telestar 15W 12573V (SR 6111) on Sunday night. Premiere on Astra 1 also broadcast 2 Sunday night games last year, the first one usually being FTA. Can't find the listings on their website for this year's coverage though.
Also keep an eye on: http://knplogic.com/sport/TR_NFL.html
Thanks for your help, I will indeed keep watching those channels. I was going to look last night, but I had to be up really early for work.
My dad has Sky and pays for NASN (I think it is that anyway), I was watching baseball on it once. He said they only show college football (which I do enjoy watching too), I don't want to pay lots of money for just that.
I will also look on Five, my brother was the one that told me they weren't showing anything (he isn't that clever and has probably made a mistake).