plants covered in a cheap little greenhouse, froze last night, down to 27 for several hours.

plants covered/enclosed in a cheap little amazon greenhouse (allot like those cheap seed starting greenhouses).

it froze last night, down to 27 for several hours.

opened the greenhouse sidewalls this morning and its clear they are sad looking & droopy, and there are frozen ice crystal bits all over on the plants, it is supposed to warm up today and the next few days-week.

are the plants going to be ok, or are they done for ?.

more importantly, will the buds be ok, or did they just get ruined ?.