In the early stage of pregnancy, if you experience chest tightness, shortness of breath and dizziness, these symptoms are caused by pregnancy reaction. At this time, influenced by the hormone level in the body, most pregnant women will experience pregnancy reaction, which will cause dizziness, chest tightness, nausea, vomiting, shortness of breath, and also easily cause general weakness, drowsiness, aversion to oil and other uncomfortable symptoms. If the symptoms are not very serious, there is no need to treat them with medication, and you need to pay attention to rest and also to a light diet. If the symptoms are more serious, you need to go to the hospital for examination, mainly to rule out other causes, such as anemia or heart disease, respiratory diseases are also prone to these symptoms, it is possible to do electrocardiogram, routine blood tests, and can also do cardiac ultrasound. If these tests are okay and the symptoms are serious, you can also take appropriate oral vitamins to relieve the symptoms, mainly with vitamin B6, and you need to pay attention to appropriate activities and go to the hospital regularly for prenatal checkups.