Reason why i may not be getting pregnant?

just incase anyone judges me or thinks i am crazy i just want to tell yous

i am 18, i am in a stable relationship, i have my own house with my boyfriend, we both have a good income, both have cars. tbh wee have a great wee life and not immature.

we are trying for a baby.. but this is what i am confused about.

we have been trying since march 2012, it is now january 2013, almost a year and there is no sign of pregnancy.

I keep track of my periods and ovulation dates, my periods are very irregular though.

when me and my boyfriend have sex the semin always comes out could that be a reason why i am not getting pregnant? and what could be the cause of it always leaking out?

i am very scared incase me or my boyfriend cant have children, it wouldnt change anything i know we would stick together but it is a horrible thought as we would both love a child.

does anyone have any advice or maybe any reason why i may not be getting pregnant? we have sex regularly have a healthy lifestyle and i dont understand why i cant fall pregnant.

thank you to anyone who takes time to read this and reply x