Hello everyone ? I've noticed that since this year I've been getting f…

Hello everyone ? I've noticed that since this year I've been getting frequent colds and sometimes a strong cough (sometimes for weeks) ?. My legs have gone numb immediately after catching a cold. Snot and congestion in my nose. What could it be? Is my immunity really weakened after giving birth? I'm still breastfeeding our little one, 1.5 years old, and used to get sick only once a year ?