pain in vagina after c section when having sex

Jg • Pregnant with TWINS after mc in April 2015 -looking forward to this journey - trying my best not to be anxious
Hey everyone,
I am 7 weeks pp after having a c section with twins - my incision itself doesn't hurt (more just a little sensitive) however my husband and I tried to have sex for the first time since the twins were born and my vagina is super sore like we couldn't continue because it hurt. Is this normal? And what could it be from?