You are not going to get pregnant again until your HCG levels drop all the way down. Once that happens you will eventually ovulate and a few weeks after that have a period. Depending on how far along you were when you had the M/C I am sure your Dr. gave you some sort of recommendation on how long you should wait until TTC again. The idea of being more fertile is not a fact, but it is not uncommon to have a M/C and get pregnant the next cycle, but it is not a guarantee. If you want to get pregnant again you just need to keep being aware of your body and look for the signs that you are ovulating and make sure you are being sexually active at that time.
Good Luck.
By the way, it is not uncommon for your period to take a bit to come back, again it is your body slowly getting back to normal.
I agree with Liz's comment above. Your levels have not gotten down yet. Then your body needs to go through a hormonal process which triggers ovulation and then your period. It IS possible to become pregnant but you most likely won't ovulate until your hCG levels are down and the normal chain of hormones take place.
After a D&C you may want to wait to become pregnant as there is a risk of miscarrying again. During the D&C your uterine lining was scraped out a lot more thinly than what would've happened if you miscarried without a D&C. So it will take time for that uterine lining to build back up.
It took me 8 weeks each miscarriage to get a period again (I've had two miscarriages). The average is 6 weeks.