The morning after pill is simply an extreme dose of the regular pill - usually 4 instead of 1 (I busted my Dr giving me the MAP which was cut from a Levlin Ed pack )

COnsidering you're BF I'd see your Dr and ask about it, but if your DH wasn't on the firing line (so to speak) and considering you're BF so regularly I personally wouldn't be too concerned about it.

If you're in doubt go to the Dr.