A whole lot of issues tail stool belly and more

[BeardieMomJ95]

So I went to PetSmart Friday and got a Bearded Dragon and he's tank and lights we're already at home. Eats crickets and collard greens really nothing else. I bathe him. Has a vet check up on the 11th
Anywho. When I got him I not certain he had stress marks he was on there with like 5 beardies and his tail at the end was all chewed and black. So yesterday that fell off and it looks back a little more further than before. Then the stress marks are still present. Now this morning his poo was more of a maroon color not exactly red with white uriate.
Then sitting on me he pooped and it was white pee then dark no color really whole thing he's never pooped on me before and when picked it up it was wet red. Now from what it looked like, Im not expert but it looked like idk when you first get your period and its really dark and such so I really think Simba might really be a Nala. But then again do reptiles have menstrual cycles? Idk I'm freaking out I want him to be happy he slept good last night the crickets he eats are not bigget than the space between his eyes standing but is the rule the crickets to be sideways and not be bigger as well? He does kinda eat too fast. They say he Might be 2 to 3 months but they didn't know much. And he eats abt 10 or more a day
But behavior wise he's really cool he's only been held by me and runs to me if he's scared. He likes car rides it's been hot out he's calm. I would add pic I'm nother sure how

 

[AHBD]

Hi there....to post pis , upload them to a site like Photobucket, then copy/paste the img/url here. Beardies do not produce blood unless there's a problem, but is there a chance that he ate something red, purple, pink like pellet food ? Otherwise he may be straining so a bit of blood comes out or he may have parasites. The feeder bugs for a baby beardie should be no longer than the space between his eyes, so you're going by the length not the width. He is acting like a healthy dragon though and eating [ although he could eat more, and be fed bugs twice a day ] So if you can, post pics of him, his tail, his set up and his poo.