Hi makeupmama (also, welcome)!
Lots of pros and cons on that. If you type 'flu shot' in the search box (above), there are all sort of opinions.
Our family opts not to get flu shots. We have been very fortunate and seldom have had issues. In fact, several years ago, my husband did get a flu shot and got sick soon afterwards, likely from the effect of the shot.
I know of others who've had the same experience. There can be bad effects from the shot, but it really seems to depend on the individual. I did a search on 'flu shot negative reactions' and there were several things that came up.
My MIL gets one every year, yet she still gets the flu every time, it seems. My sister developed Bell's Palsy several years ago, which was traced to a flu shot. These are some reasons we don't get them.
On the other hand, many people choose to get them and are just fine. I know many on this forum have had no bad effects.
It's all over the 'map' on this one. Really seems to depend on each individual. It honestly seems like a roll of the dice--odd how it can help some and harm (or seem to do nothing) for others.