I have been ill this past couple days, sore throat, coughing, chills, muscle ache, shortness of breath like anxiousness etc. This morning my throat and head are sore, mild fatigue but I coughed up sputum which was blood red. I have Aortic Stenosis. Is it just from this bug I have? It hasn't happened again since this morning, and I am feeling better this afternoon.

A thousand online doctors can't examine you online, and you NEED to be examined! At the very least, leave a message about it for your cardiologist.