I'm full of contradictions and second guess myself in this new relationship, how can I solve this?

Been with my boyfriend for a month now, in the beginning things were simpler because I didn't expect much or for anything to happen. But things are indeed happening. I think I love him but am too scared to say it for many reasons. Fear of rejection, regret, not truly meaning it, I've never been in love before I don't know how it feels but I'm definitely feelings something. I'm beating myself up over this guy because I don't know what to say or how to say it. Sometimes I feel like I'm not good enough or too young or stupid or ugly. I've never been so insecure around anyone in my life and it's unnerving. I wish I could make this stop and get past it. I don't know if the solution is to just tell him I love him or to suck it up and see what happens. Anything I say to this guy I over think it and second guess myself.