My Boyfriend Yells At Me All The Time. Take a deep breath and drink some water. Accept that you don't deserve to be yelled at.
In your case, maybe he's questioning too or just needing a little break to think about things or maybe something else is irritating him (say at work or family, etc.) that he's not talking about. Try to count to 10 and force yourself to relax with the count. Resist the urge to yell back.