How can I remember where I put something?

I went out for ice cream with my friend and she drove me home and when I got home (after I went to the bathroom) I misplaced my phone.. And my class ring!! I had my phone in the car on the way home, I am positive, because I was texting my sister. I had the ring on my finger. When I got home, I was sure I had my phone, but now that I think about it, I may not have had it... Idk. I went to the bathroom and took off my ring so I wouldn't get it wet, and I put it in my sweatshirt pocket with my phone. A while later, I checked my pocket and neither were there any more!! I hadn't gone upstairs so they could only be on the first floor of my house, and I still can't find either after searching with help from my mom!! Does anyone have any tips to remembering where I could have put them?! I need to charge my phone, so it's probably dead, so I can't call it. I'm so sad, this is a new phone! :( please help? Any tips - don't say "retrace your steps" cause i did that so many times already.