<s>[INST] Hi,I'm a 28 year old female, on nuvaring (hormonal birth control). A few days ago I had pain in bth calf muscles after a sports session, the pain in my left calf subsided less than 24 hours later, however, it is still present in the right calf. I have been experiencing some tachycardia, chest pain and shortness of breath.  Could this be a blood clot? There is no swelling in the calf muscle. [/INST] HIThank for asking to HCMI can understand your problem but your symptoms are not because of the blood clot, of course blood clot can cause such symptoms but that is medical emergency, here in your case the reason could be over eversion and the deposition of lactic acid in muscle and this will come around have soda water this will eliminate the lactic acid, take care and have good day. </s>