I would like to get a tattoo, im 18. what do you think?

I dont think that my first one should be as big as i want it. i would llike a koi fish on my above my right thigh, where no one could see it unless we were intimate. i dont want the world to see it, i just want me and the person that i am having with to know where it is. I was thinking i should get a small pisces sigh (H) behing my left or right ear, where people cant see it when i am standind face to face. the only problem with that is that my ex girl friend had one on her right thigh. I love her, and i dont know if its a good idea to get a similar tattoo even if we dont speak anymore. the zodiac is was what got us close, and she meant alot to me. i dont ever want to forget her, and i dont need a tattoo to remind me of her, but i want one. my dad hates to see tattoos on other females, but i am a girl and i want one. i dont find it vulgar, and what i am willing to get means something to me. another thing, someone said its better to get them in the winter due to the cold weather and we dont sweat as much as in the summer, is that true? I think the sooner i get the tat, the sooner i get to enjoy it. my parents flip about about doing permanate damage to my body, but i find it as art. the koi fish is what i am and who i want to become at the end of lifes journey. besides, my parents didnt leave me a choice but to get surgery on the collar bone that i broke in wrestling, now i have a scar about two inches long people can see on my right shoulder.