Hi...i Am Married...its One Year...v R Together For Last Three

Hi...i am married...its one year...v r together for last three mnths...v r trying for baby..

My doubt s i jave regular mensus cycle..but in these three months cycle gets irregular...example dec i gt 27....now i got mensus on jan 18th...and i m experiencing pain...???

My question s shd i have a change in diet or shd go 4 medical check up to have regular periods and to get pregnant....