Building trust?

I've been dating a guy for a month, and he already told me he loved me. I don't feel the same way as it takes me more time to develop feelings and trust men. This is making me very confused because I know he isn't completely open, he hid texts from another girl from me, and talks to his exes. Like I said before, we've only been dating for a month but to what point should I start worrying about his introversion? I don't want to come off as crazy and clingy, I want him to trust me and I want to trust him. How do I act?