I've been having this weird pain and heaviness in my lower chest whenever Im alone, like when Im outside by myself or just at home. It starts after a while, and then I get this mild shortness of breath, and my pulse goes up to like 105. I had an X-ray, CT pulmonary angiogram, ECG, and 2D echo, but they all came back normal. Also, when I lie down, my feet feel really heavy. Any idea what's going on?

Possible Causes
a. Anxiety or panic attacks can cause chest pain, shortness of breath, and increased heart rate.
b. Musculoskeletal issues or gastroesophageal reflux disease (GERD) might also be considered.

Recommendations
a. Monitor symptoms and note any triggers or patterns.
b. Consider consulting a mental health professional if anxiety is suspected.
c. Follow up with your primary care physician for further evaluation and management.

Immediate Actions
a. Practice relaxation techniques such as deep breathing or meditation.
b. Avoid caffeine and alcohol, which can exacerbate symptoms.

When to Seek Urgent Care
a. If symptoms worsen or new symptoms develop, seek immediate medical attention.