I'm a Pisces, yet I can;t say I love you to my bf!

My boyfriend was my best guy friend for almost ten months, up until this week when he confessed to me and I told him I liked him too. Anyway we decided to be in a relationship a few days ago. And he has already called me 'baby', 'love', and he has told me he loves me and that he must have fallen hard for me cause he thinks of me all the time and as time passes he loves me even more. That all makes me feel uneasy though. The change from best buddies to boyfriend and girlfriend is quiet weird on its own and I just can't understand how he can say I love you when he said that he has started liking me for about a month now. I'm a pisces girl and very romantic and all but I am afraid to fall in love or express my self to my Taurus boyfriend. What keeps holding me from opening up to him is also the fact that in June he kept saying how he just couldn't get over his ex and that he still loved her. I don;t want to be a subsitute of his ex but I also have feelings for him. What should I do? Is there something wrong with me? This is my first relationship by the way and I am 18.

Well, he's probably been sitting in the friend zone this whole time waiting for this moment... Whether he realises or not, unlike you he is already way ahead in the feelings department.
I think that might be what's happening here, very cute either way. =) I wouldn't buy the just last month liking thing personally.
And with the ex situation from June, well, he's probably just being straightforward with you about something that after a few relationships of your own you will realise is a fact of life.
Some exs you hate, they destroy you and debase who you are.
But others you will always love on some level. They teach you how to express your emotions, you learn through certain experiences with them and grow up together.
These things stick with you and holding on to someone is natural, but at some point you move on...
And he probably has. With you...