If you are asking yourself, "Do I have lice?" then it probably means you have been exposed to head lice somewhere. If that's the case, it is important to learn about the symptoms of lice, what they look like, and how lice are spread.
Just because you were around individuals infested with lice doesn't mean you too are infested. But then again, you may have head lice and not even know it.
So the best thing to do is have someone check you out, since it is hard to self-diagnose lice.
After looking at lice pictures to know what they're looking for, have the person carefully lift sections of your hair with a rat-tailed comb and look along your hair near the scalp. That's where head lice are commonly found, as well as behind the ears, near the neckline and at the base of the head.
Adult lice will be the easiest to spot because they are the biggest. But at the size of a sesame seed, they still aren't that big. Although lice vary in color, if you see a grayish-white or tan bug crawling through the hair, it is probably a louse. If you look closely at an adult louse, you should be able to see human blood inside it.
Look at the hair strands about a quarter inch (~0.5 cm) off the scalp. See if you can find lice eggs (often called nits) attached to individual hairs. Nits are extremely small. They look like tiny specks and will be glued pretty securely to the hair. If you see any, try pulling them off with your fingers. If you can't easily pull them off, they are probably eggs and not dandruff.
Head lice symptoms include allergic reactions to the lice bites, so you may also experience itching. Even with a thorough check, it may be hard for you to spot the critters if you've never seen nits and lice before.
If you live close to a professional lice-removal business, check with them to see if they will do a lice check for you.