My wife had a c section and we recently had sex and now what it sounds like my penis can't be accommodated by her vagina like it's not expanding propr?

Postpartum sex: Women may have issues post partum with sex due to a variety of issues. Infection, dryness, not being adequately stimulated may all be issues. First, lots and lots of foreplay to get her vagina ready. Second try a water based lube the first couple of times and don't necessarily expect to finish. Also, make sure she's at least 6 weeks out from c section. She may need to see her OB/GYN as well.