Oral thrush

Does oral thrush hurt babies when they are feeding? (Bottle fed) My son was recently prescribed nystatin for his oral thrush and it’s day three but he recently started becoming fussy during feedings. I posted earlier but didn’t think to ask. My other kids never got this so it’s new to me. Is there anything I can do to comfort him or we just have to ride it out? He’s 8 weeks 6days and will only eat about 2 or 3oz then get too fussy and sleep for about an hour or two.