Most provinces have a nurse hotline you can call for medical advice, I'm not sure what province you live in but you could Google "healthline" or "nurse hotline" or something plus the name of your province to find the number. Like in BC, for example, you can call 8-1-1 to speak with a registered nurse, who can help you decide the best course of action and whether or not you need to go to the ER. It is a super useful service, I have used it on a number of occasions and in my experience they actually give good compassionate advice and aren't just like "go to the ER" about everything.
We can't really tell you over the internet from a brief description how serious it is, it's best to err on the side of caution and get medical treatment. I do understand not wanting to sit in the ER waiting room or walk-in clinic for 6 hrs, but surely you can see a doctor sooner than 10+ days, do you live in a very small isolated town or something? Only thing I can think of for you to do at home is apply hot compresses to the injection site. I have hit nerves before and had no permanent damage, but that isn't always the case. Doctors will often just say "see if it gets better and come back in a few weeks if it isn't", and if it's already been a week since you injected they may not be able to do much as far as things like flushing the injection site, but as I said, best to go to a doctor soon in case there is something they can do.
