I just started feeling tired. i am 26 weeks pregnant and haven't felt like his since the first few weeks of pregnancy. is this normal?

26 wk pregnant/tired: The early part of pregnancy produces much more progesterone than in regular cycles, and tends to make one "sleepy" or "tired". At 26 weeks, you are not filling up your lungs as much or as often with oxygen b/c of limited excursion of your diaphragm, so one feels "tired" with even moderate exertion. Check with your ob provider, as anemia can also cause this effect.