Immune system after miscarriage

So I had a miscarriage back in April. I work at a daycare and since the miscarriage my immune system took a beating, I'm constantly sick, and it's always the worst stuff like stomach virus's lasting days and bronchitis and walking pneumonia, has this ever happened to anyone? I visit the urgent care at least 4 times a month if not 2 times a month. My boss is actually pissed I called off today but I have bronchitis and I'm working with infants. Not only is it a lot more work in the baby room (I already feel like I'm breathing through a straw) but we have a few months old and i don't want to get them sick.