Radiotherapy side effects apart from tiredness ? Any one experienced them?

Thank you for the explanation @arpie
As that was not spoken about at the meet the Dr appointment at radiology oncology last week, when I got information over load on what comes next ! 
It’s my left breast 
that will be target area 
it’s very very overwhelming 
and my head is spinning 
😵‍💫 
it’s getting all a bit to much to deal with 
but thank you for your response