Hello, I know the feeling that you are refering to. When I was pregnant for the first time with my daughter I was never tired and never had to go to the bathroom like they say you do, but that all changed with my son. My husband and I tried for about a year to get pregnant and then when we weren't actively trying anymore I ended up pregnant. I would be so tired that I would wake up at about 2-3pm in the afternoon and go to bed at around 6-7pm and would feel as if I had worked a 14 hour day. I am certainly not a doctor, but I would guess you may have a bouncing baby boy within the next year. That's just my guess though. I hope it all goes well for you.
I'd get tested for anemia. It can make you so tired you can barely walk across the room. If you are sexually active, also try a pregnancy test. Early on in pregnancy, some people get very sleepy especially in the early afternoon.