Good on you, spud!!!!!!!!!!!!!!!!!
As jon' suggests, it might not hurt to have a triptan, too. If the nasal spray works for you (as it probably will) for backup to an O2 system, that's great. If only injections work, be aware that you can reduce the physical and financial consequences very significantly by getting three shots from each autoinjector. We can help you cross that bridge if you come to it.