I've been feeling more tired and have some difficulty speaking. when should i see the doctor?

Difficulty speaking: The most common cause of "difficulty speaking" is shortness of breath. This is usually a sign of serious illness including pneumonia, blood clot to lung, heart attack, asthma, heart failure, or other severe allergic reaction. You should see a doctor promptly for shortness of breath. Fatigue is a separate problem. Most people can cope with it if it is short-term; after 2 months, see a doctor.

Right Away: You may have a condition which could be treatable and which could worsen without intervention. The speech problem is particularly of concern. You probably need some tests to make certain it's not anything serious.

Don't Wait: In a person who has not had speech problems the development of problems with speech is an important matter. It should be evaluated as soon as possible.