Enlarged swollen lymph nodes in few regions, or systemic lymphadenopaty , could be due to other virus, bacteria or parasites infection, as well as due to some inflammatory systemic diseases, malignancy or even as a side effect of using certain medications.
Negative HIV test after 6 months period of possible HIV exposure is usually excepted as a reliable result.

See your physician for complete check up and finding the underlying cause for swollen lymph nodes!