Bad scraping grinding noise when moving in reverse

Hi, a month ago I got two new tires put on my front end and last week I had my cars oil changed and it was inspected at the Hyundai dealership. Today I was in a parking spot and when I put my car in reverse I had to push the gas harder than usual to make the car backup and it made a terrible grinding noise. I thought it sounded like noise was from the front passenger side. I have a loose plastic piece n my wheel well there that had got caught and torn by my tire a while back. I assumed my tire was catching that again but I had my sister look and it wasn't she couldn't see anything at all. The cars done this a CPL times today anytime I park at a store n go to back out. But It makes no noises going forward and goes just fine. I out the car in reverse from drive and the car backed up just fine with no noise it only seems to do it when I go from park to reverse. I am a single mom of three and I can't afford to pay a mechanic to find the problem right now. I'm hoping someone here can tell me what it is so I can check into fixing it myself or if I know the issue not having to pay to diagnose it and only paying for the repair night be feasible for me. I'm praying it's something simple this is my only car I have two special needs children with lots of doctors appointments and I cannot go without a vehicle. Please, please help me!