Are you supposed to be able to feel lymph nodes in neck? I can feel a few in my submandibular/submental regions. All are either 1cm or smaller. I've heard conflicting views on this. 25yo f. Healthy.

Sometimes. Lymph nodes in the neck may be felt under normal circumstances and more so if you are fighting off a respiratory infection. 2 cm +, tell the doc.
Not uncommon. You are describing what we call shotty nodes, a result of a viral infection or oropharyngeal infection. If they stay smaller than 1 cm, they can be observed. However, if you notice more lymph nodes or they increase in size, you need to see your doctor.
Usually benign. Inflammatory reactive nodes in neck and jaw area are quite common reaction to upper respiratory or oral infections. Most people are not concerned about lymph nodes that are not greater than 1.0-1.5 cm in diameter. Not to worry unless get much larger or do not regress.
Yes palpable. Lymph nodes 1 cm and smaller are generally ok. You may just be noticing them and they were always there. If you are otherwise healthy then it should be ok. In nm you may be exposed to different pollens and ground soil bacteria. Your lymph nodes protect you. Hope this helps.