Something is off. The appointment happened, or the test was ordered, or the symptom has been there long enough that it can no longer be explained away. No one has said anything definitive yet — or something was said that raised more questions than it...
Mindfulness-based therapy does not ask for the abandonment of past or future. It asks for something more precise: an awareness of where attention is actually going, and whether that place is worth the cost of being there.
When anxious thoughts are showing up we are often 'time traveling' to the past or (especially) the future. When this happens, ask yourself "how am I - right here and right now?" Be honest with your answer. Often we are OK right in this second,...
Check out this article for some tips for handling anxiety around public speaking. https://blog.hubspot.com/marketing/science-public-speaking-tips