Brief Answer:
Teeth, ear, salivary gland infection.

Detailed Answer:
Hello,
Thank you for your query.
I'm Dr. Shuba Hariprasad & will be answering your query today.

From your query I take it that the lymph nodes under your chin/jaw are swollen with a swollen lower lip.
The lymph node swelling could have either caused the the lip swelling or vice versa.
In the former scenario, an infection near the area of the nodes (tooth, gums, inner lips, oral mucosa, throat, even ears) can cause it to swell.
When this does, it can, by pressure effect cause the lip to swell.

If there are any problems with the lip (an insect bite or a wound - both of you mentioned you don't have) this can cause swelling of the lip followed by swollen lymph nodes.

The difficulty in swallowing makes me favor the first possibility (lymph node swelling causing the lip swelling). I am also concerned that this may further impair your swallowing further & your breathing as well.

I would have examined you carefully to rule out any infection (dental, throat, ear), do some blood tests (complete blood count, Erythrocyte sedimentation rate, C-reactive protein). Additional tests based on clinical findings.
I would check your swallowing reflexes and breathing pattern.
As you have already done, continue to observe for any reaction, inflammation, difficulty breathing. Avoid possible irritants (like your cream) and see a doctor if this persists for more than a few hours or if it gets worse.

If you have facial swelling, difficulty breathing, hoarse voice, visit the ER right away.

Hope this helps
Please let me know if there is anything I could help you with. A photo of your lip, & nodes & throat if possible, may enable be to be more helpful

If you do not have further questions, please close this discussion & rate my answer.

Regards,
Dr. Shuba Hariprasad

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