You'll be fine, AlisonM. 🙂
Insulatard is available as pre-filled pens, cartridges for use in pens or vials.
Personally, I would never use a pre-filled pen, mainly because it seems a huge waste of resources, but also because prefilled pens take up a heck of a lot more space in the fridge than cartridges. Of course, if you have hand co-ordination problems, you might find pre-filled pens easier, but in my epxerience, it's no more fiddly to change a cartridge than a needle - and I do both at the same time 🙂
Be prepared to make up a case for your pen, spare cartridge(s) and spare pens, as supplied carriers / cases are never convenient, in my experience - a pencil case is cheap and lots of patterns / sizes are available.