It's like the first trimester all over again, except that you're so big and clumsy, your symptoms may seem worse.
You're sleepy, but you just can't sleep. It's getting really hard to find a position that doesn't press a 5-pound (2.27-kilogram) baby onto something inside you, making you uncomfortable. If you're already having trouble getting comfortable sleeping at this stage, build yourself a nest of pillows so you can sleep while propped up. It doesn't sound that comfortable, but chances are, you'll get sleepy enough to make it work.
You're feeling that shortness of breath again, just like in the first trimester. This time, it's not caused by the hormones so much as the fact that your uterus is pushing on your diaphragm, and it's hard to draw a deep breath. Aerobics can help, if your doctor says it's OK to do some cardio.
Your vision may seem to be failing, too. The fluid behind the lenses of your eyes is building up, and you may end up more nearsighted or farsighted than usual. Obstetricians often recommend that you wait to change the prescription in your glasses until after the pregnancy, when this should clear up.