What are you taking it for? For everything I used to take frequent antibx for, including a long-term prophylactic regimen my daughter was on, I've found ways either to avoid the infections or, on the rare occasion they occur anymore, to treat them by megadosing vitamin C.
Yes, you should hit the probiotics hard. The best you can buy (Garden of Life Primal Defense, BioKult, those are some places to start looking). Fermented foods, too. Playing with the gut bacteria should not be taken lightly. I didn't feel any effects my first year, either, but now, ten years later, I'm still fighting to restore my health.