Stress or .... ?

I can't seem to be able to control my emotions very well. I'm not sure if it's due to stress, exhaustion, lack of sleep or I'm merely losing it.

I get very agitated and emotional at work over trivial matters and reflecting after I couldn't tell why I reacted in such a manner. I've never been this way prior.

The little guy have been falling sick way too often, aug to oct he has gotten Roseola, influenza A and even hfmd. Ain't  I a lucky mummy? With him constantly ill I had to take time off work and be his primary caregiver and that nearly drove me up the wall daily. 

I'm not sure if it was pure exhaustion that I constantly imagine hurting him by smashing him against the wall so he could just give me a moment of peace or was it something else.

I'm seriously doubting myself if am able to restrain causing him any harm. That's my biggest fear.