Hello, Thanks for writing to Health Care magic, I am Dr , Muhammad Ahmad , I have read your question closely, I understand your concern and will be helping you with your health related problem. Low levels of thyroid hormone causes stress and depression, when a patient starts taking Levothyroxin , one might get some mood issues as levels change in the body so does the mood to but it takes time to stabilize. You can always discuss with your doctor about anti anxiety medication. If oxygen saturation in your body is fine then all you need is to avoid taking stress, anxiety makes you feel short of breath, plus your metabolism is changing now a days due to higher levels of hormone in body , this can cause strange feelings. There is nothing to worry just keep taking medication and visit your doctor regularly. I hope this answered your question, If you have more queries I am happy to answer you. Regards. Dr.Muhammad Ahmad