Would you get bends? Divers get bends when they come up from deep sea too quick. But the pressure in the deep sea is many times atmospheric pressure. The difference in pressure between space and atmospheric pressure is only one atmospheric pressure. In addition, bends comes from nitrogen forming bubbles in the blood IIRC. I don't suppose astronauts would breathe much nitrogen, just low pressure oxygen. Could be wrong of course.
I don't know, not my area. I was thinking the drop from 1 bar to zero is clearly a smaller differential than a diver coming up will experience but it's more sudden, i.e instant.
According to Google, astronauts just breathe air from tanks. I don't think human lungs work efficiently with low volumes of pure oxygen so have to have something inert mixed in. I understand divers have different mixes for deeper dives to reduce the nitrogen bubble risk but there's no such issue for astronauts as their suits keep atmospheric pressure.