Your current situation is not heading to lymphoma. But you can not ignore it , as lymphadenopathy is a feature of local infection/ inflammation. So better do a physical consultation. Hope it will help.

Is there are additional symptoms of fever, weight loss, night sweats ?

Yes, for the above details mentioned, there is no reason to suspect Lymphoma. Level 2 are most commonly enlarged group, in most children and adults. Even size cut off to call it increased size is 1.5cm for level 2, while for other levels in neck is 1cm. Unless there is a generalised lymphadenopathy or systemic symptoms, no reason why one should suspect lymphoma here.

Any fever? It should be inflammatory as the size is decreasing.