Where did this pain come from?

Here I am the day after chemo, and I think I am doing really great.  It isn't unusual for me to go grocery shopping the day after chemo, or even to be doing light house work.  So, this is pretty normal for me. Except today I feel a LOT of pain in my arm and I am bloated on my right side.  (liver maybe?)   The crushing tiredness has not yet kicked in.  But I feel it creeping up much faster than it usually does.  Plus I am finding myself a bit more grumpy and sort of tearful than usual.  What is the deal with the emotions huh?  It is not something I am enjoying.  Let me tell you what (to quote Hank Hill)

That is all that is going on here.