Is it normal to be so boy crazy?

I'm in a relationship but my boy craziness will never go away well probably later but not anytime soon. I'm just 21 and I have that young spirit where if something gives me that exciting feeling I get attached and all I wanna do is pursue that feeling hence boys. However, I already tried being single after breaking up with my bf and I didn't like it. I'm not the type anymore to mess around for a while, I like something stable. So I'm back with my bf knowin what I want now which is to be with him but being long distance for now does make me feel more free. I tend to be flirty but cause that's all I can do. I mean if a guy attracts me I'm like a little kid, I get these sparks and wanna play with them but since I can't I honestly just have fantasies what it would be like with that guy. Obviously it's not as bad as cheating but it could still be considered wrong yet I still do it cause it's safer. What doesn't help either is my bf isn't the type I usually go for but because he's so sincere and I do love him and he's my best friend I'm with him. Then all these guys who are my type come my way. It's hard being in thi relationship and I know if I let him go again I'm just gonna go back running to him unless I found another guy who is my type AND gives me the comfort my bf gives me.