i think ur too bothered about the timing..... try longer foreplay and understanding what makes him tick is important.... when guys get too arouse they will lose control.... so even as a gal u can control when he comes.... like when u know he is cumming.... stop cool down... by pulling it out and just cuddle and kiss.... then when is less arouse start again.... if he cums half way.... nevermind try again.... pratice makes purfect
to really enjoy its not only the time when he goes into u.... its the whole process from the seduction.... to the foreplay... then to the intercourse
try guiding him to really understanding the whole process.... like us Bros here none of us here will know so much unless we tried and learn from pass experience
take it as a learning step for the both of u.... explore each other.... learn and grow together
Just my 2 cents okie