Yes, those creaks and bumps and other sounds you hear from your lovely domicile can be a little unnerving when you are by yourself can't they? BWAHA HAHAAHHAHH! Don't be afraid little one it is just your home trying to tell you things or even ask: "How was your day today?" Stay online then, if you're still uncomfortable. It is not unusual for pretty little things like you to be scared when home alone especially at night.
What your experiencing is anxiety. Most likely, separation anxiety. You need to figure out what triggered it for you & get peace of mind for that issue, then if the anxiety still continues talking to someone about your situation can also help, be it a counselor or friend. If it gets really bad, your doctor can put you on anxiety meds. Good luck
If this has only recently been happening, ask yourself what's changed. New neighbors? Did you see something disturbing on the news, or in a movie? Hear any strange sounds? Understanding where the feeling comes from may help you get over it.