My immune system seems to be pretty good strangely enough. I haven't been sick all winter, besides one minor cold (knock on wood). Besides what is going on with all this sensory ****, brain fog, and weakness I'd be really healthy! HA!
My immune system is pretty strong still, but I know someone with Lyme whose immune system is pretty run down: I don't know what makes the difference in different people. In the years since I got Lyme, I haven't even had the sniffles.
Sore soles can be a symptom of bartonella, a coinfection that sometimes comes with Lyme. I had that for a while long before I was diagnosed, but never tested positive for bartonella, so don't know what it was.
Cracking neck and ankles -- absolutely. I sometimes feel sore and achy in the mornings too -- can't quite correlate it in time with 'flares' of Lyme or die off of the bugs, but it must relate somehow.
It all sounds familiar to me. My jaw makes cracking sounds that other people can hear.
The immune system is weakened by lyme and the co-infections so the body may not be able to fight off other infections very well. This is why people with lyme can have infections like EBV along with the lyme.