It may be easy to brush off these common complaints as nothing, but sometimes they can signal a serious problem. We went to the experts to find out when it's time to go to the doctor. Here's what they had to say:

1. Sleep problems: Amy Korn-Reavis, respiratory therapist and sleep technologist, cautions you should not ignore sleep-related issues. "I have been working in this field for a long time. I believe one of the things people do not talk to their physicians about is their sleep problems," she says. "If a person has heart issues, diabetes, or high blood pressure and they have issues sleeping, snoring, or high levels of fatigue, they should talk to their physician about it."

If you don't know where to begin and are suffering from the conditions mentioned, Korn-Reavis suggests using an Epworth sleepiness scale or a Berlin questionnaire and discussing the results with your doctor.

2. Vaginal discharge: Alyssa Phillips, physician assistant and bone marrow transplant survivor, knows firsthand what an abnormal vaginal discharge can tell you. "I didn't ignore or delay seeking medical attention when I began having a watery vaginal discharge that I thought was just a routine bacterial infection," she says. "Turns out, it was a really rare and aggressive type of cervical cancer called Large Cell Cervical Neuroendocrine Cancer." She was in Stage IV at the time of her first symptom and seeking medical care immediately saved her life.

3. Constipation: Almost everyone is constipated these days. Did you know each of us should be having one to three bowel movements a day to be at our best? "When we go several days without [going number two], it could indicate a blockage, tumor, or prolapse in the colon," says Dr. Kathy Gruver, author of The Alternative Medicine Cabinet. "This should be checked out by a physician."

4. Headaches: Although we're all familiar with the occasional headache, it can sometimes also indicate a serious problem like a brain tumor or meningitis, says Dr. Gruver. If your headache is accompanied by a fever, stiff neck, or vomiting or lasts an unusually long time (more than a few days), it should be investigated, she says.

Other symptoms that require medical attention: A severe headache that comes on suddenly; a headache accompanied by slurred speech, vision problems, trouble moving your arms and legs, loss of balance, confusion, or memory loss; a headache that gets worse over a 24-hour period; a headache that occurs with a head injury.

5. Tooth and facial pain: Dr. Gruver has had several clients who have had facial pain and were misdiagnosed. "They went from dentist to dentist to find out they ultimately had shingles in the facial nerve," she says. "Because it wasn't treated quickly, it led to painful and permanent neuropathy in the face. It could have also lead to blindness."

6. Diarrhea: It's gross-no one wants to talk about it, but you should if you're experiencing diarrhea for longer than a few days. This could indicate a serious problem, like a parasite, Crohn's disease, cancer, pancreas or gall bladder problems, and more. Dr. Gruver points out that simply taking anti-diarrheal medicine is not the solution.

7. Acid reflux: One in four people in the U.S. suffer from acid reflux, but just because it's so common doesn't mean you should ignore it, says Dr. Carson Liu, board-certified surgeon. "Acid reflux can cause heartburn, dental erosion, and asthma-like symptoms when stomach contents are aspirated into the lungs," he says. Plus, it can lead to esophageal cancer.

"Popping a few pills doesn't seem like a big deal, so the quick fix is the go-to for the vast majority of people suffering from the condition," he says. This quick fix is only masking the condition. Acid reflux is a progressive disease and becomes wore as the anti-reflux valve in our esophagus deteriorates. Talk to your doctor about the best treatment for you.