Newly diagnosed

My boy 4 yrs old. Just last saturday he was showing signs of muscle spams and stiffness. he pants occasionally but not everytime. Hes been on crate rest since until we see the neurologist. the emergency vet gave us gabapentin 200mg three times a day. Predisone start tmrw.. they originally gave us Carprofen but told us to switch but wait a few days cuz they can't be mixed. Since this is the first week on meds.. is it normal for them to have breakthrough spasms in the early stages? After the episode, he's fine. He can walk, eat and urinate no problem. Please any input helps.