Starting Valium dosage - need help - feeling sedated

I did a direct cross over from 1 mg of Ativan to Valium. The first day I replaced my nightly Ativan dosage with 5 mg. The second day I took 2.5 mg twice a day and then 5 mg at night. For the last four nights I've taken 2.5 three times throughout the day and then 5 mg at night = 12.5. It’s my fourth day doing this and I’m starting to feel pretty sedated at certain parts of the day as the Valium really kicks in.  I’m 5 days into this process and wondering how to tailor it. Do I just continue with 12.5 and then once fully stabilized start a slow taper or can I go back down to 10 mg?  I went up to 12.5 the second day because my anxiety was out of control from the terrible interdose withdrawals from Ativan and my doctor made me do a direct crossover. My anxiety has quelled quite a bit, but it’s 9 pm and I’m supposed to take 5 mg at 10 pm and my eyes feel very heavy and tired and I just feel drugged.  Any advice would be greatly appreciated and then how to taper down from there. I’m two months into this process and want the drug out of my body.

Maybe try reducing by 1mg? I crossed over from 20mg Oxazepam and was completely drugged out at 10mg Valium. I settled at 8.5mg and was still feeling quite droopy, but I didn't go lower as I had anxiety from hell before to C/O.