Issues With Milk Supply at Night!!!

Kristin • Married 8/16/14💍 Pierce Jaxon: 6/5/16💙👶🏼 Logan Marie: 2/27/18 🎀👶🏼.
Hi mommas,
I am having a problem. Little man is 11 (almost 12) weeks old and is EBF. We barely bottle feed (with BM) but I do want to keep a stash on hand because my husband and I have noticed that he sleeps better when we give him extra milk in a bottle at night. So I pumped tonight and only pumped 0.8 oz total (from both boobs)! 😳 I have always had a dip in my supply at night and noticed little man cluster feeds a lot but I didn't know it was this bad. This could explain the horrible nights we have been having. What do I do to get my supply up at night? By 4 am both breasts are engorged and hurt and are plenty full. 😞 so I am not sure what I am doing wrong but I am worried and feeling like somehow it's my fault. 
Thanks for your help!