Hi. From your symptoms one of the possibilities is a condition called congestive cardiac failure. There may be many causes either related to the heart or lungs. You may get tests and investigations done such as B type natriuretic peptide . Echo cardiogram and chest XRay are also initial investigations. Certain types of lung diseases such as emphysema , bronchitis etc over a period of time put pressure on the right heart producing similar symptoms. Therefore investigations are necessary. You may also require a Doppler study of your carotids to look for blocks in there. Medically called stenosis. ECG studies and imaging of heart blood vessels also . Best regards