Clutch Frozen?

[yaris2010RS]

So this morning was one of the coldest days of this winter here in the GTA. i woke up to a -26ish *C with wind chill. my car is parked in the garage, although it is not heated it does protect it from the wind and it does feel a tad bit warmer then outside. i have about a 50min drive to school and about 40 of those mins i couldnt use my clutch. it was very stiff, wouldnt come back up, it would very slowly return and my leg actually got tired (i have used rigs before and it was stiffer then those clutches)
when first pulling out of the garage and to the gas station i didn not notice any issue, after filling up my car with gas the clutch was stiff. it was very hard to move and continued to be like this for the next 40 mins. it slowly got a bit better then it got light again, almost instantly.

i have had this happen on another cold day before but it went away as soon as the cold light turned off. i am assuming this is caused as the hydraulic fluid gets colder and thicker but does anyone else have this issue? annd also with the fluid thicker and the pedal stiffer, what damage can this cause to the clutch cylinder (i dont know if that is the correct term)