Something really creepy happened when i came home today from shopping

Me my mom and my brother went shopping today. and when we came back i realized the glass door that goes onto the deck was broken (the window door was 2-layered). like it was like shattered, but it was still together in one piece. (i though the door looked kinda shiny) so my dad got home and he checked it out. it kinda looked like it was the weather. but it wasnt the first time there was this kind of weather (we've had to door for about 2 years). it also looked as if someone threw a rock, but the net outside wasnt even touched.

another possibility was that someone was trying to break in, cause where the crack looked like it started was near under the door handle. but then i thought "if i was trying to get in i would break the glass right next to the handle not under it..."

it was really awkward. but it looked really pretty and it was shiny *_* and it looked like ice (but it was glass) it was almost like art (in a way i guess)

i dunno, it was pretty creepy (cause this was like 10:30 pm and it was dark)
anybody think they know what happened?