It’s important to note that the aim of mindfulness is not to get rid of stress or anxiety, but rather to help us become more aware of our situation and react to sources of stress in a calmer, more considered way.
The better you become at being mindful, the more likely you are to be able to respond calmly to situations as they arise, and the less likely you are to become overwhelmed by negative emotions. You can even take a test to estimate how ‘mindful’ you currently are during the day!