Tori - I very much sympathise with you.
I also am 3 months pregnant with my second. Archie is only 8 months and as a result am constantly knackered. Poor husband is pulling 80+ hours a week at work to enable me to only work part time so really (and very understandably) gets frustrated when I'm so fed up that I seem to not even notice that cleaning needs doing. One evening I burst into tears when he got home as Archie had been crying solidly and for no discernable reason for over 10 hours. I try not to mention things to him as I feel he has more than enough of his plate as it is.
I was hoping that when I had my scan I'd feel a bit more can-do about the pregnancy as so far I've been dreading the arrival and really regretting getting pregnant so soon. This makes me feel really sorry for the baby-to-be.
We had a check up today and heart the foetal heartbeat and I actually started to feel something which was a relief...
One thing I've been doing is throwing myself into my photography and it has been cheering me up as I feel like I'm actually achieving something for a change - something tangible but not as fattening as baking.
Perhaps, should you have the time (hah!) there's something you used to enjoy that you could shoe-horn into your day.