There are 2 questions being asked here- could this bump had been a recurrence?, and could you have given your HSV-2 to your BF?. Two answers too:
1. Could this be a recurrence of HSV-2? Hard to say, recurrences do tend to follow a pattern so that if this did not resemble prior recurrences it is unlikely to have been. In addition, it sounds as though it did not go on to form a blister and you were examined by a health care professional who felt it was unlikely to be herpes. All of this makes it unlikely it was a recurrence, BUT
2. Even without a recurrence, in theory you could have given your infection to your BF. This is because the virus can be present on normal appearing skin and in that way be the source of transmission to others. On the other hand, most exposures to HSV do not lead to transmission so taking all into consideration; my guess is that there is little risk of having given him infection. If he does not develop lesions within 10 days of your exposure, you did not give him infection.
Now for advice on how to deal with this from here on out.
1. He should have a gG-based blood test such as the HerpeSelect or the Trinity ELISA to see if he has had infection in the past and is unaware of it. If so, there is not need for precautions; his infection will make him resistant to getting it from you. If he has not, then precautions which will minimize his risk should be considered. These precautions, which have additive effects, are-
A. He needs to know that you have infection
B. You should not have sex if you think you might be having an outbreak.
c. You should consider taking chronic suppressive therapy for prevention of transmission. It will reduce the probability of transmitting infection by 50%
D. You should use condoms.
By taking these steps, the likelihood of you transmitting infection to a susceptible partner are close to zero
Hope this helps. EWH