Check with a cardiologist. If your heart is not working properly, it can cause fatigue, nausea,dizzy. My son is nauseated everyday when he wakes up. Sometimes he can get out of bed at noon, sometimes not until 6:00 at night. He is scheduled to see a cardiologist in 2 weeks, at the urging of his psychologist. He has been dealing with this for 3 years. He saw a gastroentrologist, then a neurologist, then of course when they couldn't figure it out, it must be anxiety. So they referred him to a psychologist, who says it is not anxiety.
If this doesn't pan out, then they want him to see an Ear,nose throat doc. Inner ear??
Check for celiac issues. The intense tiredness/fatigue is a symptom that is seen in many with celiac/gluten issues. And many of your other symptoms are consistent with celiac, too. Check to see if anyone in your family - extended family - has food intolerance issues.
You may want to consider trying a gluten-free diet for a couple of weeks to see if it's of help. Cut out wheat, rye, barley, oats and malt in any form from any source. You won't see changes over night, but if you see small indications that you're feeling better stick with it.