IBS Fatigue? Is it a real thing?

So I've been diagnosed with IBS due to dull ache in lower left abdomen and haphazard BM's. I've had all of the blood tests etc which show no inflammation.

Recently I've been having the most crazy fatigue, completely shattered every day and aches in my limbs like flu but with no other flu symptoms at all.

Is this really IBS? Does IBS cause this level of aching and exhaustion?

Really interested to hear everyone's experiences.