Should I be concerned about the repair to a ceiling after water damage?
During our renovations we had extensive leaking through our very old plaster (c1927). We found that even after the plaster had dried, the stains would continue coming through. We had the ceiling treated with a stain blocker before painting but still some stains came through.

On the ceilings with the least damage, the stain blocker + a few coats of paint worked. The plaster was as strong as ever. For the badly damaged ceilings, we ended up replacing the plaster. 

For us the decision was easy since the plaster was so old and kinda wobbly.

Long and short: you should be ok but wait until it is totally dry then apply a lot of stain blocker before painting.

PS: Also check the state of your insulation (if you have any)