He said "just let it happen"

Agh lol my fiance && I were talking last night about ttc (going on month 14 :-( ) && he told me to calm down && just let it happen, how do I do that when I want another baby soooo bad && we've been trying for soooo long?? && to top it off I had a dream last night that I got a bfp :'( in my daily life I tend to be suuuper stressed, && then ttc && get af every month just makes it worse && depressing....idk how to relax && just let it happen!! :(