hang in there! I'm in my 4th month and still sleepy in most afternoons. After work I immediately take an hour nap. if not I'll have a headache. Socialising with my colleagues at work makes time past faster, and I rest whenever I can during weekends. you can do it!
I was also very very tired in my first trimester.. could easily jst sleep off anywhere.. isit possible to request wfh, or taking a nap during lunch etc. ? If its really causing you to feel unwell, perhaps taking a medical leave to rest off?
This is the first trimester where you will feel fatigue. It will get by soon. Just have to push through and do what you can. It is tiring but we have to be positive with our mind. Otherwise can be so draggy our days.