How harmful would it be to take MDMA after a 150mg dose of DXM, 2-3 hours later?

2 hours ago I took 150 mgs of DXM, REALLY low dose because I thought I had nothing to do, so we popped 10 15mg pills. Now we have something to do. Uh oh. Is it safe to roll on 1 pill after about 3 hours of a 150mg DXM dose?