Is it normal for two friends to be so affectionate?

I've been friends with my friend for around a year and a half. I'm a lesbian and she's bisexual. We're both in our late teens. We didn't see one another for a year (jail and family issues, moving around) and just started hanging out again recently after we both moved back to our original cities. We've always been affectionate. We sleep in the same bed and spoon when we're over at eachothers houses. We tell eachother we love one another. I always tell her how pretty and beautiful she is and she tells me the same. We've made out several times and she even went down on me once for just a second or two. We hold hands and stroke eachothers hair. We share clothes and change in front of one another like nothing. I was holding her last night after something happened and asked if I could kiss her because I really wanted to after we told eachother I love you. She said yeah but just a peck. So I did and of course it was amazing if not short. The two of us are around eachother every opportunity. Whenever I ask what's up with the kissing and everything she says she doesn't want to talk about it. Her friend lives down the street but she only hangs out with me. She told me she only really trusts me and her family. I'm the same way. So is it normal for two people who are just friends to be so affectionate?