Illness/Sickness: Red Spots on Tail ??!!

[sylvia00sanity]

So I've kept exotic and unusual pets for a long time and have kept them all living healthy and long over there expected years. I always do a couple months worth of research in advance of buying my pets and keep all my animals in check with regular maintenance and health checks. Every thing from sticking my hand into a pythons mouth to check for respiratory problems to long and annoying water testing for my fish and amphibians and it was then when I noticed something unusual about one of my newest additions.

I received 3 baby axolotls about 3 months ago and on one of them i noticed red spots along its tail which I'm quite concerned about. All 3 of them are eating and behaving properly and as usual. The spots aren't quite large ( i say only about 1mm - 3mm in length ) and I thought maybe it was an injury like a bite from another axolotl (which iv never seen them do) and at first it didn't worry me since the water was already treated with things that would help in that - since one of my axolotls were already injured, scratched and missing a hand on arrival (which it already regenerated and is perfectly healthy).

Then I considered it to be an infection and at that point i started freaking out, worrying about my other two baby's. Needless to say red leg then came into mind and since this is the first time one of my pets could of actually got sick I'm not sure if I should take it to the vet or do a treatment by my self or if there's actually nothing wrong.

Any Answers,Suggestions or Tips would be Awesome !!
Additional Details

Here is a picture :
Flickr: sylvia00sanity's Photostream

 

[Bellabelloo]

Could you possibly add another photo please ? I can see the dots but can't tell exactly where they are

 

[sylvia00sanity]

Sure thing will do once i get home.

 

[sylvia00sanity]

Sorry for the wait but here are my new pictures and I'm not sure if I'm imagining it but it seems the spots have got better ?
Flickr: sylvia00sanity's Photostream

 

[Kaysie]

Do you test your water quality? How big is your tank?

Is there anything decoration-wise it could've gotten stuck under?

 

[sylvia00sanity]

Yes the water quality was good and regardless I did a 3/4 water change, the tank is quite large and is almost 2m long , about 80 gallons equipped with a no current filter.

Decoration wise, I use regular beach sand as the substrate, along with clay hides and floating vines which would prove to be incredibly difficult to get stuck under

Unfortunately this morning upon feeding, I noticed that the red dots have now formed a line!
I have added another picture.

Flickr: sylvia00sanity's Photostream

 

[Olivia97]

Yes the water quality was good and regardless I did a 3/4 water change, the tank is quite large and is almost 2m long , about 80 gallons equipped with a no current filter.

Decoration wise, I use regular beach sand as the substrate, along with clay hides and floating vines which would prove to be incredibly difficult to get stuck under

Unfortunately this morning upon feeding, I noticed that the red dots have now formed a line!
I have added another picture.

Flickr: sylvia00sanity's Photostream

when you say beach sand do you mean taken from the beach or just regular play sand?

 

[sylvia00sanity]

Now that I think about it I'm not sure, It's just a regular giant bag of sand I bought from my local fish store which was suppose to be safe for all fish and amphibians. There's no labels on it or anything.
Sorry, that's all i know. If the sand is an issue I can always take it all out.