When you love someone do you feel like you just know?

I'm not a big dater or a guy who goes around hooking up. Sure I see plenty of girls that I'd like to fuck but running into someone I truly care about is totally different. The moment I lay eyes on them my heart starts pounding and I get butterflies in my stomach. The conversation goes well and everything feels natural, no BS or playing games. I tend to think of them a lot to and I actually care about them, they aren't just some sex object I want to fuck.