probably not a great idea to mix DXM with lithium or with abilify. Abilify actually uses the same enzymes that break down DXM, so if anything your trip should be prolonged and different in nature.
anyway, sometimes DXM can take 2-3 hours to kick in. You sit there forever thinking it won't hit you, then you take a bunch more only to realize the first dose you took is really starting to hit you. Do not make that mistake.
The drugs you are scripted don't have major interactions AFAIK with DXM in terms of killing the trip. Abilify may alter the nature of the dxm experience but should not inhibit it. In any case, i wouldn't mess around with DXM if you are trying to control symptoms of a mental illness, DXM can throw you for a loop and make you unstable if nothing else.
No swimming here and given DXM's dirty pharmacology i wouldn't combine anything else with it, scripted or not. Since you're on a relatively low dose of abilify you'll definitely feel the dxm, but don't dose any more or do high doses of DXM while on abilify, it may potentiate it way too much.
do not mix DXM with abilify in the future, it's not worth the risk of serotonin syndrome or extreme potentiation, even at just 5mg/day.