Your short story experience should provide good discipline in tight writing. Don't become wordy just because you have the room. When you need to add length to the novel, throw another obstacle at your MC, bring in another character, or have your sub-characters get involved in sub-plots that intertwine with the MC.
Another issue you may run into is the complexity of a novel. Find a method of keeping track of what you're doing. I use two methods.
First, I give each scene a descriptive title such as:
# INT. Police Detective Squad Room Thu 6/26 0745
When the MS is ready for presentation, I make a copy and I delete all but the "#" in the scene title.
Second, I use MS OneNote. I use it to describe my characters, keep my outline, write notes for revision, list research sources, and anything else I need to keep me on track with the MS. Others use notebooks, index cards, spreadsheets, and several other methods.