Probably the vents...

Something happend to me,I heard a groan in my house with nobody here,but my sis,my sister was awake,and she doesn't groan,I was next to her,and it didn't come from her,next thing you know,the dishwasher opend by its self,it was locked, next,my dog passed out,and when it woke up,she started to bark at the wall,nothing was there,when my parents got home,everything got back to normal,when it was 4:00

I keep hearing creaks its probably the vents

It good