Sperm can live in the body for 5-7 days so yes, you can get pregnant outside your ovulation window. 

Sperm can survive in a woman up to 5 days in the best environment only. If you're not in your fertile window, there is to much acid in the vagina and the sperm die off. Once you have sex in OR Close to you're fertile window and have the perfect environment (ewcm) sperm will make their travels and will be able to sit and wait for the egg. Although several do die off, there are plenty that make it.