Hey ladies am i screwing things up?

ok so i have this female friend. shes an amazing freind and we have known each other since junior high but didnt even become friends since this past year or so through fb and then just talking etc. well anyway. im shy and timid so i dont have alot of female friends. so this is not an area i have alot of expertise in so if i sound like an idiot well thats why. so yeah i joke around alot with her i guess u could call it flirting a bit not sure never really flirted intentionally. so yeah sometimes i tell her how i fond her cute/attractive sometimes i joke around about wanting to see her in a bikini since she never wears em. im juts playing around an she knows it but i huess my question is is like my flirty joking around gonna mees things up like is this a no no in a male/female friendship. im not trying to sleep with her or anything im just kind of blunt from time to time . i dont wanna screw things up can u help please. we dont have feelings for each opther like that and she has a bf. so ladies help please even though im 18 im dense when it comes to this stuff