Perbezaan sakit contraction nk bersalin dgn false contraction

Mcm mana nk bezakan contraction nk dekat nk bersalin dgn contraction biasa?saya dr semalam perut asyik keras,pastu ok..keras pastu ok..perut rs mcm sakit jgk kdg2..awl masuk 7 bln ada jgk rs mcm ni tp jrg2...skarang ni npe kerap n dh start rs perut keras tu mcm sakit...please share your opinion.1st pregnancy,34weeks++