Question

Possible, but very very unlikely if you’re taking it properly! Most birth control is about 99.7% effective!

There is always a chance especially if not taken correctly

There are always a risk of getting pregnant from using just one method. The size of the risk depends on how good you are with following the instructions for taking it. When you follow the instructions accurately, the chanses are very very very small. For most modern pills for example, one couple out of 200 will be pregnant after a full year of using birth control. That is is an extremely small risk. It means that about 1 failure out of 2,600 28 day cycles. Without the birth control, over 90 out of that 100 couples would be pregnant after a year.Using two methods together makes it as close to 100% safe as you can get. So birth control pills and a condom, or a non-hormonal IUD and birth control, or an IUD and a condom. The chances of two methods failing simultanious is for all practical purposes zero.In order to fully enjoy the pleasres of sex, it is important to feel 100% safe. So do whatever makes you fell protected.

Yes. Nothing is 100% unless you are abstinence.