Loss of progress from skipping injections?

I'm wondering, if anybody's ever needed to skip their injections, how much of a setback it is? I need to miss one for work already, and I'm a bit worried about actually getting the chance to inject on a few other occasions; I basically can only guarantee one of my injections for the month of December (and I am on a weekly dose). I'm curious how much this could hurt my progress? If it wouldn't be a massive setback, it may frankly just be easier for me to skip injections while at my parents' house or traveling for work..

Edit: Thanks for the advice everybody! I hadn't really considered toiletry bag possibilities for at my parents' house because I considered a sharps container (even a makeshift glass bottle one) too large to discreetly carry past somebody, but I may be able to make it work. As for the business trip, there are a few other factors which pile up to make it pretty much not feasible to do the injection there, but I did discuss that week with my doctor who said that given the circumstances I am pretty much better off skipping, at least for this particular trip. I'll definitely take the advice to get them done in the surrounding weeks with holidays etc though, I basically just needed to hear solutions from outside myself to realize some of my concerns weren't really relevant)