Good for you. NMM seems to always have clients for the new boats they buy so the money goes to work immediately and is accretive to earnings the same quarter. Hopefully this time it is the same. If you believe in NMM's long term potential (which looks good for the next year, anyway) you should definitely buy on dips that are presented...like this one.
I, too, will be buying another thousand for my portfolio. Lower price opportunities like this happen about 2-3 times a year. It's easy to acquire a lot of NMM over just a few years!