Help! 22mo male keeps getting sick since August

I know they say you’ll get sick a lot once they start daycare but my son has literally been sick almost non-stop since the end of August. We’ve only gotten about 1 week of rest between each illness (rhinovirus, covid, rsv, influenza, strep, ear infections, norovirus, ect). The latest one to hit was Norovirus on Sunday. One day after finishing a second antibiotic course for a double ear infection that has been antibiotic-resistant (Of course the doctor is unavailable for a follow up for a month so we’ll have to guess if it worked). I was also giving Nasonex in order to clear the congestion he never cleared from the past illnesses. Today, he’s tired, sleeping more than usual, crankier and more demanding than usual and not sure he wants to eat normally yet. His ears seem to be bothering him but they won’t do anything unless there’s 48h of fever so. Also, he’s constantly constipated despite eating a high fiber diet and I keep getting dismissed when bringing it up at the doctor’s because “it’s extremely common” but he’s been having issues since 4mo and it’s touch and go with restoralax and glycerin suppositories to try and manage it. I’m not sitting in our ER with a 24h wait time for that. He’s still breastfed, so you’d think the ear infection risk would be lower. I was supposed to stop a while ago but he’s just constantly sick so it never seems like a good time. What am I doing wrong? Is it normal for him to be constantly sick? We’ve been sick alongside him and have barely been able to work or send him to daycare. Edit: he’s gone down from 33 pound to probably around 29.5 if I were to weight him today… it’s concerning to me.