paranoid again

See my last post for the full story, but the TL;DR is that I fell into septic shock (surgery infection related) at the end of January.

I just saw a friend yesterday. She hugged me, and then only remembered halfway through several hours of convo to tell me she has a scratchy throat. Sure enough, I wake up today with a scratchy throat. Now it's night time, and it's worsening (irritated sinuses, swollen lymph nodes, extra fatigue). No fever, but I do feel like I've been hit by a sack of bricks.

What signs do I look out for? I don't want to run into the ER with a common cold, but I don't want to slip away again.. I don't have the luxury of caregiver supervision this time and I'm scared of losing my proper judgement again. is there any symptom that can confirm it's probably time for the ER? Fever, etc..