Umm... See DXM is a nasty dangerous drug in high doses - just one time and it can cause permanent damage, depending on the dose and your tolerance that is. It is essentially a weaker version of ketamine hence it's "likeable" effects, but it also shares the same toxicity profile, actually, even worse so than it. After one dose too high, taking all factors into consideration, including body weight, fitness level, health in general etc. you could end up with a bladder problem. Have you ever experienced incontinence or the inability to pass urine after taking DXM in the past? While 3 times in 5 days is next to nothing compared to some, it could still be a large problem for you as everyone's body make up is different.
All I'm trying to say is that be very careful with this stuff. It's not really discussed much (and I don't know why either) as to how dangerous it can be- but try and limit your usage as much as possible and keep doses as low as possible too, who knows, it could end up saving you from having to use a catheter for the rest of your life to piss. DXM is a dirty drug.