Flying with prescription in checked luggage to spain?

planning on travelling to ibiza next month with my meds, currently on a 30g script via mamedica.

Will the travel letter be for the whole 30gs?

will it be okay to just put in my suitcase with a copy of the travel letter and prescription, don't want to be smelling of weed on the plane or when im checking in and cant realy be fussed with needing to pass it through secuirty etc when can just go in the case.