Wonder week and nursing

Okay so my lo is 12 weeks and has been fussy, clingy and very sleepy which I can usually deal with easy but he's not nursing every well. He'll nurse for a few mins, then the only way I can get him to finish eating is with the shield. I hate using it because I feel as though he doesn't get as much as he does without it. I had him weaned off it completely and I can still do some dream feeds without it. I was just wondering if anyone else has gone through this... a what you did to help