buserelin injections ivf

Hello everyone I'm going going through FET at the moment, now iv gone and got my self a pickle I'm doing my driving lessons and I got one at 12 today I'm supposed to do my buserelin injection at 1 my lesson is for 12 till half 1 it's not absolutely essential it has to be done at that time as it isn't a trigger or anything however I would like to do it at my normal time, I'm not sure whether to do it at half 1 when I get back or just be before 12 !!! Hellp!! I can't phone as the clinic is shut till Monday x