I used STM of NFP to prevent pregnancy for 12 cycles before we achieved our first planned pregnancy, so I had 350-400 experiences with checking my cervix for position, firmness/softness, and degree of openness. I began checking fertility signs again around 7 weeks pp, when I simultaneously had to leave the baby to return to work and also began having sex again. My cervix was waaaaay more open at 7 weeks than it had been before pregnancy, and it took about 7 months for mine to close up (during infertile periods) to the degree it finally settled on. As in, my "closed" cervix is not as closed as pre-pregnancy, but there has been no more closing since about 7 months.
Are you having pain during intercourse, or feelings like your cervix is being bumped?