Will my husband I have a healthy baby after loosing baby with chromosome abnormality?

We lost our baby girl a month ago at 14 weeks due to a chromosome abnormality. We were told we had been very unlucky! I am 25 years old my husband is 24, i always believed this was something that happened to older couples! We have had tests to find out if its something in our DNA and are still waiting for results. I have just had my first period since and we want to try again straight away. Should we wait for results or just go ahead? Our results might take another month. Could it be that our DNA is not compatable (as iv just read about in someones question). Our doctor believed it was just bad luck but i wanted the tests as my auntie also lost a baby to the same chromosome abnormality (trisomy 18). I have a daughter from a previous relationship. Has anybody been through the same thing or got any answers please.