Hello... Welcom to HCM... According to your complain you have problem of small amounts of blood in cough that may be because more exertion during coughing... Mention a consistency ,amount and duration of cough that help in diagnosis... Respiratory infection cause blood in sputum problem... Cancer condition blood in cough also present.. . Consult a pulmonologist for further diagnosis... Detail history and investigation give exact idea... Auscaltation helpful for diagnosis.... I hope my guidance helpful to you.... Take care. Thank you.