Yazsaydin bunlari yazmak zorunda kalmazdin..

 there was no need for you to write these (things) if it were you that wrote them

changed my mindas I think yazsaydin means that you are not sure if  it was she who he who wrote them , am I correct

If you wrote these, you wouldn´t need to write.

or

If you wrote, you wouldn´t need to write these.

Thanks for the huge correction caliptrix I dont think I will ever get this language

Don´t worry. This sentence doesn´t haven a meaning so clear alone (solo/itself). We need to know what they are talking about.