Does sexuality change over time? ?

[Johnny]

I think my sexuality change constantly. On Monday I was straight, there is a girl in my English class, I have a crush on her when I first saw her, she's damn pretty, just my type, we caught each other staring, I think she likes me too, I'm really shy when she was around. So the next day, there is a very cute little guy in my French class, I have a crush on him too, and I think he also does, I told him he was cute, and he said I was cute too, he asks me if I have a gf, but I said no, we get along really well, I think he gonna ask me out sooner or later. So for a couple day later, I think I'm asexual, my mind was completely free from sexual gf, bf stuff, nothing at all, concentrate on my study and work. So it's just going around like a circle for awhile now. Question: if both of them ask me out at the same time, how could I handle it? I really like them equally, no more or less, I can't loose one or another.