It sounds like you had a very intense and vivid dream that left a significant emotional impact on you. Dreams that evoke strong feelings, such as fear, pain, or anxiety, can often feel very real and take some time to process upon waking. This is not uncommon, and many people experience similar feelings after particularly vivid dreams.

In your dream, you exhibited a protective instinct towards your friend, which may reflect your deep care for those close to you. The act of saving your friend but suffering an injury yourself could symbolize feelings of sacrifice or the fear of being unable to protect loved ones. The physical sensations you experienced in the dream, such as pain and nausea, may indicate unresolved stress or anxiety in your waking life.

The ringing in your ears and the heavy nausea could represent overwhelming feelings or situations that you are currently facing. The fact that you can't remember which friend it was might suggest that this concern is more about your relationships in general rather than a specific individual.

To help process these feelings, consider journaling about the dream and any emotions it stirred up. Writing down your thoughts can often provide clarity and help you work through any lingering feelings. If the anxiety continues to affect you, it might be beneficial to talk to someone you trust about your experience. Remember, it's okay to seek support when processing intense emotions.