Advice needed

So this is something I've struggled with for a while now, and I've gotten to the point where I have no idea what to do about it... So pretty much, I've got this really close friend, let's call him Mike, though we don't hang out much, he's one of my closest friends, and we can talk about anything with each other. We're also both planning on going to the same university next year. Then comes the fun part, I have developed allot of strong feelings for him over the past few months, but I have no idea what to do about them, I don't know if he's into guys, and dont know if I take the risk, admit my feelings, and possibly alienate my closest friend, or leave as is, and keep him as a close friend, and just hope my feelings die down..... Gotten to that point of absolute desperation and have no idea what to do Edit: sorry about formatting, on mobile