I take methotrexate weekly for ctd. i am on levaquin (levofloxacin) for sinus infection. is it best to skip my weekly methotrexate injection or not? having no fevers

Yes: It is prudent to hold the Methotrexate when being treated for infection. However, given the rate of metabolism of methotrexate, it probably makes little difference whether it is held or not.

Probably not: I usually have patients stop biologic medications (enbrel, etc) if they are on antibiotics. I usually do not have patients stop Methotrexate in this situation, but asking your rheumatologist for their advice would be a good idea.