First I recommend waiting about a week longer, processing the emotions you feel towards something first before you make a decision is important.
Secondly, if you decide that you no longer feel romantically attracted to your bf, my best advice is bringing it up lightly. You'll need to be clear and firm in your decision. Especially if you still want to be friends afterwards. If you don't wana be friends... well it's up to you how you want to treatĀ him when talking about this lol
Either way I wish you the best of luck!