Breastfeeding is always a very important factor for the baby and mother and  many times there are some problem faced by mother because of either wrong position while feeding  lack of proper diet stress related factors. A proper is counselling is required which can be done by a lactational counsellor along with a proper diet with plenty of liquids some supplements may be helpful like shatavari . Also try to avoid giving top milk in initial stage specially with bottle feeding which may be the culprit for lactational failure most of the time .

Breast milk is best for the baby.Please consult a lactation nurse/pediatrician in person.Formula feeding should be the last resort.Hope it helps.