nauseous and out of breath?!

So I feeling like I can't eat anymore without me being nauseous all the time and been out of breath like if I walk somewhere my heart will start to be fast and be out of breath.... 😥😥I'm getting scared... My period ended a day ago .. So I don't think I can be pregnant 😳 Should I go to the doctor v? 😩 Also I'm crying all the time like I'm crying for any little thing😥😥😥