Fasting being given priority over nafl ibaadat

I would like to fast and try and see how far I can make it. The problem is that when I tried fasting last year, the medications I take for epilepsy are much stronger without food so I end up waking up after 11 or 12 noon most of the time and then don't have much energy for tilawat, zikr, etc.

Should I give fidya and put my tilawat, zikr, duaa, etc. first or fast? For me it's a matter of nafl or fardh, which is more important, the fast or the ibaadah and tilawat?