You can become pregnant anytime of the month though the possibility is higher at certain times during the month in regards to your cycle.
You can try one of the two options mentioned by the above poster.
Yes, condoms breaking can cause pregnancy, especially if you're in the middle of your cycle. You have two options - if it's been less than 72 hours (but better if it's less than 24 hours) you can get the morning after pill. It isn't 10% effective and can mess up your cycles, but that's your decision. Other option, is just waiting it out and if your next period doesn't show then you would need to take a preganncy test and see if you're pregnant or not.