How do I go about buying a spare vial?

I've been on TRT Cypionate & HCG for 5 weeks after an up & down 8 month stint on clomid. I have a habit of forgetting to re-order my prescription for medications finding myself with not much left, don't want that happening here. How do I go about buying a spare vial oof Cypionate as my clinic is subscription model so doubt they'd let me. Also a bit conscious it's glass, drop it and i'm fucked. Oddly they let you buy two vials of HCG at a time which I'm also on. Have asked for a copy of my prescription.

UK