There are many ways that you can react, many will simply work through it hoping it will go away. Sometimes that works, sometimes it doesn't but I can guarantee that your muscles will not forget what had happened so that annoying "tweak" can turn into a long term problem depending on your activity patterns and amount of stress/tension that is placed. So what should you do when you come upon this scenario? Self help and possibly a little therapy. First things first when you injure yourself ICE. Ice helps to reduce any possible inflammation. If you have a muscle pull or sore muscle then you need to add moist heat. Let me remind you that this is not regular heat but moist heat. This can be a rice bag or an electric blanket that has a dampened towel placed between you and the blanket. The difference? Dry heat only affects the surface whereas moist heat penetrates the muscle and brings blood into that area which, coupled with the ice, creates a manual blood pump. This encourages fresh nutrients to come into the area and start repairing then the ice takes away the by products.
Alright, what else can be done? Well I highly, highly recommend using Arnica essential oil. This can be purchased locally. I assume that many aren't well versed in the uses and potency of essential oils. That is okay. I was in your shoes and skeptical too that is why I tested it out first. To begin Arnica oil is noted for it's anti-inflammatory properties but it also helps to prevent bruising. This is your best friend and it helps to have it in your first aid kit for sure!
Now we have iced, heated, applied Arnica oil, what else? You need therapy. (That's the Ramsay in me coming out) Our bodies are amazing! You have a weakness and your body will automatically compensate in order for you to keep going. This is good in that and doesn't slow you down, but also gives people a false sense of security. You still need to address the weakness either through self myofascial release or massage therapy. Preferably both.
Wrapping things up you need to listen to your body and take care of yourself. So get your stuff in gear and keep your body moving!