Feeling tired

It is Thursday 10/25. Last weekend I had three injections of Gamunex-C three days in a row. I had them SAT, SUN, and MON and didn't feel too bad. On Tuesday, I knew I wouldn't be able to go in to work at my desk job. So on Wednesday, I got up and went in. I could tell right off the bat I still wasn't up to snuff. So, I took some Ibuprofen and I was going to stick it out. By mid afternoon I was really dragging bad. So I went home a couple of hours early. I still feel a little drained, and I've been pushing liquids and caffeine, and I hope to make it all day today. Does anyone have any dietary suggestions for me. I am new to this board and disease. The support here already has been great. Much thanks.