If you feel extremely uncomfortable with what you wear, change it and don't wear it. Of course its going to arouse you sexually if your that sexually sensitive, but you have to have self control. Don't put yourself in a situation you may regret. You have free will to wear whatever you want, but some things do have consequences. I still for myself would rather wear a bathing suit. I don't care who thinks what. It is for MY comfortability. What is comfortable for YOU? That's what you need to ask. Also wither or not it sends the wrong message. Also don't be by yourself when at the beach. Overall be careful.
I was after my breast grew one summer when I was fourteen, it took a year for me to be confident enough to wear a swimsuit. Like im super skinny 4'10 and have 36ff breasts. The attention and admiration I get from guys feels amazing though I act like I don't want it and dress modestly. I met my fiancee at the beach aged sixteen he was 28 and he was instantly attracted to me in my swimsuit, he says the fact that I can stand up defys the laws if pyshics but guys will be guys you know its all tits and ass with them and after they've got theirs then they are interested in your personality.