Tiredness, Body Pain, Weak Appetite, Sleepiness, Fast Heart Rate, On Multi-vitamin, Typhoid Fever History, Thalassemia-type Alpha. Serious?

Question: Hi, I am a supervisor in my work place, it require mental and physical strength during hard days, which happens more than more often than I like in the last 2 months. lately, I notice I am not feeling as well as before. I am only 27, I used to be able to wake up and feel fresh and new, ready for anything but in the last month, every 2 weeks I had to called in sick 2 days in a roll, because I feel so tired, my body aches, no appretite, sleep alot, but not feeling any better, supplement doesn't seem to help much, my head hurts from time to time, and dizziness and slightly fast heart rate sometimes follows. I take multi-vitamin, so I wonder if there is any other vitamin I am missing. Often when I rest at home, it doesn't seem to help alot. I have been working even if I am unwell since I know my work place need me. I had a history of thpoid fever a couple years ago, which was cured quicky after 2 weeks, and I have thalassemia-type alpha from my mom. It never gave me any discomfort before.
Is there something I should be more concern about? I am seeing a doctor soon, just no appointment available now.