Pre ejaculation

Katie • 20 year old nanny in love with my best friend for 4+ years !
My boyfriend and I have been together for 4 plus years, we have sex like crazy.. All of the time... does anyone else expirence your husband or boyfriend only lasting 5 minutes or less? We are in our 20's and wondering what could be wrong or if there is anything we can try to prevent it... He try's so hard but it just ends up coming out (; haha 
Thanks ladies !