Well, I thought I would update on my little revelation before.
Have decided to remain monogamous, but have said we can't remain oblivious to my tendencies, that I would like to be able to develop something in the future if something comes up. He agrees and said it's probably good to apply the same to him. For now I've realised I am completely happy with my man, it's still only early days for us and I want him to myself for a bit longer, without having to share my time around.
Thank you so much for your replies, you've all helped me figure out what's going on in my brain! I felt totally at peace and happy when I realised what I wanted so am confident I'm doing the right thing for me