@Wouldloveanother We've been going through this too. I read all your posts/replies and it's like you're describing my eldest DS (Aug 2019 baby), he even has the viral-induced wheeze and inhaler. We now have another baby (Aug 2021) and honestly, it's been hell.
Eldest DS was with a childminder and none of the baby/toddler groups opened until Sept/October 2021 so he was doing fine illness-wise despite mixing with lots of other childminders children at the parks and at other childminder's homes. Just the odd cold here and there, nothing too exciting.
Since the baby and toddler groups re-opened it's just been one thing after another and it's been hell. Now he obviously has his little brother to pass all his germs onto and I swear we literally haven't had a healthy house since Easter this year. I've been practically stuck at home with an ill child (poorly, temperature, contagious) pretty much non-stop since then. I've had a few days here and there where everyone has been healthy enough (myself included), to be out and about. A lot of my friends are/were pregnant, or have young babies. Plus elderly and immuno-compromised family... so I've felt incredibly isolated.
Same as you I've been to the doctors numerous times and they say it's normal. Kids are basically making up for the lack of mixing and they're getting 2 years' worth of bugs in a shorter time period. I can definitely believe it's worse for you if your little one has been in a nursery the whole time.
I keep hoping we're past the worst of it but my youngest is going to be starting childcare in a couple of months.
Honestly, I considered returning to work earlier than planned from my maternity leave cause at least that way me and DH would be sharing the caring duties rather than it all falling to me.
You have my sympathies. I hope things improve for you soon.