Dear Mari,
if you are regularly having this type of scenario, you can directly make a custom transaction code starting with Z or Y by using above mentioned BAPI_GOODSMVT_CREATE with directly excel sheet. You have to guide the user to enter all the values in sequential columns(make template), keep some control parameter in system program not to load the same twice.
System will create material document and display the created document number once upload is done.
R,
Amala