My boyfriend isn't in love with me yet?

I've been with my boyfriend for about a year now, and I know I'm in love with him. I've told him a few times but have never heard it back. I let it go for a while but finally asked about it last night. He said he knew I was going to say something soon, and that he doesn't say it unless he 100% means it. He said don't take it the wrong way but he just doesn't feel it yet. He's only ever said it to 2 girls he's dated before, and I guess that means he's being cautious because those two girls treated him pretty badly in the end. I told him it was okay, and that all I wanted was to know. I told him that I've been very happy with him and that I'm glad we have each other. He ended up saying that he was glad we found each other too. I'm not too worried about it, I just hope that one day he does feel the same way. Should I be worried? He's 26 and I'm 25 btw.