DD is 8 months, have bfed her up to now but I think my supply must have gone down. Complicating factor - am 8 weeks pregnant, she has been ill and I think is now teething but wants to nurse all the time. Fed at 1am,4am, 5am and 6am today and I just don't think is enough there for her. Would it be so very very bad to do evening or dreamfeed as formula? Or will I undo all the good I have done?