My submandibular gland hurts. when i went to the doctor for a check-up all she said that it got bigger, nothing else.does that mean i shouldn't be worried? what should i do?

depends, does it swell intermittently or after meals? could be sialoadenitis (gland swelling/inflammation/infection) or a stone perhaps, not all stones are seen on radiology, so the typical "get a scan" doesn't always yield results. as a minor in the US (dunno who is legal adult in your local area/country) would suggest followup, esp if foul taste or swelling after meals, followup with PMD/ENT