Is It Safe To Take Fluconazole And Doxycycline Together With Fearfully Low Kidney Function?

I have compromised kidney . I was given fluconazole by my GI doctor foe 7 days for candida - fungal infection . Today , my lung doctor gave me doxycycline 100 mg for lung infection . Is it okay to take them both same day ? I still have 3 days to take my meds for fungal infection ,and going to start today the doxycycline 100 mg for lung infection . Is it okay to take them both same day . The lung doctor said he gave me small dose since my kidneys only 40% working now . Help me .