If your this tired, I absolutely wouldn't worry about your other symptoms that are probably temporarily gone. Extreme exhaustion is very normal in pregnancy, and a good sign that things are on the right track.
There isn't much that you can do about the fatigue that your not already doing. You are making a human, of course your exhausted! You will feel less exhausted in a month or so when you begin the 'golden trimester'. Good luck!
I have been trying to take 1-2 walks a day to help with feeling so tired vs. sitting at my desk. It doesn't solve the issue but helps a bit. I think even a 5-10 min walk can make a difference.
With my first pregnancy, I was working and also very tired. I would even go out on my lunch and take a nap in my car in the parking lot! Also, I would take a 30-60 minute nap when I got home from work, to keep me going through the evening. I remember writing in my notebook at about 8 or 9 weeks that one morning I woke up and the first thought in my head was "I'm not pregnant anymore" - all the symptoms that had finally shown up at 6 weeks were suddenly gone. I was still pregnant, and they did come back, it must have just been a blessed reprise. I wouldn't worry about the cramping too much if it's not too strong and you don't see any blood. I was just speaking with my dr. this afternoon and she said if it's a pain I'm not familiar with from other times in my life (I often get sharp lasting pains near where it seems my ovaries would be), and it goes away within 24 hours or so, not to worry. Call if it's unusual pain. Hope that helps.