There are a lot of wonderful online resources about tongue-tie and lip ties. Instead of reinventing the wheel, I will just list some of those links here.
Possible signs of tongue tie and lip tie:
Pain, low supply, blanched or flat nipples, mastitis/plugged ducts in mom, thrush that keeps reappearing
Low weight gain, reflux, colic, gassiness, breaking suction often while nursing, clicking sound while nursing, poor latch, refusing to nurse
Examining Your Baby for a Tongue Tie or a Lip Tie:
Is Treatment Always Necessary?
What Happens during a Tongue Tie Laser Revision?
Aftercare for Tongue Tie Revision (ask your health care provider what he/she recommends)
What should you do if you suspect your baby has a tongue tie or lip tie after perusing the above links? Contact your local IBCLC for an assessment and referral to a pediatric dentist or ENT experienced with diagnosing and treating tongue ties and lip ties.