First, Heaven and Hell is the Abrahamic afterlife concept.
Artemis is Greek, and the afterlife in that pantheon is the Underworld. And everyone goes there, good or bad. There's more complication to that, but another story for another time.
The Roman historian Livy had an idea that Lupa wasn't actually a Goddess. Yes, Romulus and Remus were two little boys adopted by a She-Wolf, but Livy claimed that she wasn't even a wolf at all, but a woman. When the farmer found the two twin boys, he was also married to a woman. Lupa or Lupea is a Latin name for "She-Wolf" but interestingly it's also a title of a common prostitiute in ancient Rome. So over the years, the She-Wolf could had been warped into a Goddess in some people's eyes.
Back to your original question, it isn't a bad thing to follow two different Goddesses. I work with a mix of pantheons, so it isn't shamed. And don't worry about where you'll end up, just appreciate what you currently have in life.