Nope, most recommendations are to not start solids until 6 months anyway. At 5 months, my daughter had no interest in food other than the fact it was sometimes in front of her while I was eating and she might pick it up (just like she might pick up anything in her reach, but wasn't because she was 'hungry'). In fact, even after we started to offer her food at 6 months (finger foods), she didn't really show much interest or eat much more than a small bite until probably 7 months. Now at 13 months, she has a great appetite and loves her food, but I think it's in part because we didn't push it on her or stress about it. Personally, I'd not worry about it for another month or so and then see what she does.