Hi and welcome sorry that you are unwell. I have a question when you say the result is 120 do you mean 1:120? Normally, ANA test results are given in this form.
1:40 is negative, 1:80 is considered a mild positive, and then they double on up from there, as you can see with this pattern 1:120 wouldn't be the listed form. It's possible he/she meant 1:1280, which is high , but are you showing any symptoms of lupus? If you go to www.lupus.org and look at the symptoms, you must have 4 out of the 11 to get diagnosed with lupus.
If you are not having any symptoms of lupus I wouldn't worry to much, if a person is sick it can make your ANA positive. If you are having symptoms or are really worried have your Dr referr you to a rheumatologist.
Hope you get some some answers and I hope you feel better soon.