No trademark help please

I have a product I designed myself so it’s not being sold on Amazon and private labeled with my brand name. However I have no trademark and apparently there is another brand that just recently started selling under the name I chose. However it is under a completely different category and also is in all caps whereas mine is all lowercase (not sure if this makes a difference) What will happen now? I private labeled all my items and purchased GTIN under the brand name as well. Please help!