Aw, first time mom anxiety, totally get it! Every pregnancy is different talaga, some tummies show earlier, some later, kaya hindi lang based sa months kung gaano kalaki dapat. A few of us tried worrying the same thing, pero ang gyne namin always said as long as baby's growing okay sa ultrasound and you're gaining weight properly, you're fine! Best to bring it up sa next check-up mo with your doctor para ma-confirm na lahat normal lang, especially if this is your first time and you're not sure what to expect.