Advice..

I had a miscarriage a few months back and I didn't tell my boyfriend for certain reasons that I regret now.. but mainly because I was just really scared, and we're both young... we were only 16 and 18 (now 17 and 18 as of last week)... I told him last night. And he says he's fine but I know him and he's not… He said he would talk to me later, that he just needed time to process things.. And I totally respect that I want him to process things and take what time he needs. But, I'm afraid that I've REALLY messed up.. I kept this from him then out of no where i just drop this big bombshell and... I don't know what to do. I don't want to lose him.