Saline nose drops

My boy (16w) has been struggling with a viral infection bronchiolitis & he’s been prescribed with saline nose drops yesterday & after I gave him the drops (1 drop to each nostril) he had some blood coming from his nose, today a bit more. Is this Normal after the drops. I gave him over the counter nose drops for babies before & this didn’t happen. Maybe I should stop using them because they irritate his nose?