I got a flu jab recently because I am a person who is very compromised regarding that specific illness, and I think my body was threatening Flu quite hard.

I got the runny nose, I got the achey limbs, I started getting the head pressure and all this stuff, but I didn't entirely believe it was actually the Flu, so I just really treated myself well by doing a lot of low-impact exercise, eating well, getting the ole vitamins in my diet and resting lots.

I think what I got was a compromised persons reaction to a thing I'm compromised to :)

I would still always get this shot, even if I got real Flu from it even. It's not worth the terror I live in around anyone with a cold .etc in winter (too many people are idiots when sick so you never quite know).

It also probably helps that my particular form of being compromised to Flu is very chronic Asthma instead of an immune disorder.