Being in a relationship is physically and emotionally taxing, and if you aren't ready for it, it won't work. If, like you, you don't feel you even want it, you'll save yourself a lot of hassle by not being pressurised into it. There's nothing wrong with it, a lot of people enjoy being single, others like being in a relationship, it's just the way we are.
Good on you for not feeling like you have to be seeing someone.
Would people say that if you aren't looking for a relationship, girls can pick that up, even if you are only subconsciously telling them?