Most EEPROM use a cache page of 8 bytes. You may encounter all kinds of problems if you try to write the same page in two subsequent write operations.Thus, I think it will be better to go with multiples of 8. Meaning you will use 40 instead of 38 in this statement: "Posicao_Memoria = Posicao_Memoria + 38". And the rest of the code should obviously go according to this. And yes, you probably need 10ms pause anyways.

Have a look at the datasheet to understand the difference between page write and byte write. You will find some other valuable informations too!

J-P