Someone walked into the house last night

I’m alone petsitting for my parents and very stupidly haven’t been locking the doors as they do not typically do that either. Last night at 2am I woke up from what I believe to be the front door closing very softly. I then heard footsteps and my overnight bags being looked through.
I ended up slipping out of bed and locking the door before calling 911 on speaker. At some point during the call I heard moving downstairs which may have been that person leaving, I made sure my presence was known. The cops didn’t find any obvious evidence of an intruder.
I want to think I hallucinated this, but I could hear exactly when their heels lifted up to take another step. I could hear my reusable bags being crumped just like when I go looking through them. I understand that many intruders will leave if there is signs of someone awake, but I do not want to think of what could’ve happened if that wasn’t a deterrent.
Anyone have a similar experience?