Nursing moms pregnant w/ #2

I breastfed my now 2yo for a year. When I had a let down my nipples kind of got a weird tingle sensation almost like a pinching feeling.. now that we are trying for #2 and I'm ovulating/ had sex a couple times I'm feeling a very light let down feeling.. is it my imagination or could I possible be pregnant !!??? I've never had this feeling since I quite nursing a year ago.