Ha, been there! I thought about it right away as well, then floated the idea to my husband when my first was 7 months old and without even having made a decision, I found myself pregnant that month. I did conceive while breastfeeding, just a month or two after my period came back (which seemed to coincide with my son getting more interested in solid foods). Just keep in mind that your milk supply will drop if you are nursing while pregnant. I wasn't prepared for that but luckily had a good frozen stockpile to supplement with.