I was a mild case, stayed home for 2 days, right back on my feet after that. 32M, no health issues. Symptoms just lingered and lingered. They would go away then come back days later. Mainly sinus pressure and dizziness. Then 4 months on I started getting intense chest pain and shortness of breath. Cardiologist noted some abnormalities but was not concerned. Put me on beta blockers. Fast forward to today and I still have shortness of breath, some cardiac symptoms, and random pains in my left arm and back. It really eats into my quality of life, but I am thankful I don't have it as bad as many others.
I keep tabs on the long haul community to see if researchers have figured anything out/others found anything that helps. So far there really isn't much. I'll note that there are a surprising number of people who aren't aware they are long hauling (they "recovered" and then months later developed issues - not making the connection until stumbling upon another long hauler) and that people are really hostile about the idea of long hauling. I don't know if it's a coping mechanism or what, but people want (need?) to hear "I fully recovered" when they ask how you are doing. I don't tell anyone except those close to me about it, it's completely not worth the debate they are going to want to have about the validity of my symptoms. It's pretty common in the LH community to not be publicly upfront about it because of this. There are plenty of people who know me, know I got sick, and will relay that I fully recovered.