I sent my friend a text asking him if everything was ok (in Turkish) and he replied:

"Sen benimim için oldun" (he was probably a bit drunk)

I understand what it means translated literally but do not understand what he actually means.  Can anybody help?

Tşk ederim

it is not possible to undestand what he means at least not without seeing you first text. maybe his answer is related to your question in which you may asked some other thing???

I think he wanted to say "Sen benim için öldün"="you are dead for me"

or he mihgt mean "you are ready for me " " you are convenient for me"  as translation of "sen benim içim oldun"

My text read:

"herşey tamam mı?"

I was asking him if everything was ok as I hadn´t heard from him for a couple of days