haha, wow! vede 3 kere post yapmisin sen lan! cici arkadasim benim, BANANE BJK hala buyuk bi bok! cok sansli oldunuz, git onu kutla!

haha , wow, you sent that post 3 times (what is LAN defined as?) my sweet friend, i dont care BJK are still a big crap! very lucky it happened, go celebrate it!

Translation is correct.

Lan(or, ulan) is an exclamation, used in slang. It doesn't have a direct meaning in English but sometimes it means "hey!" or sometimes it is used in the sentence when somebody is angry. There are no rules for this. You can use it at the beginning or at the end. But it is slang