Open Question: what is wrong with my boxer puppy?

i got my puppy 2 days ago she is a 3 month old boxer . i noticed her really shy at First when i got her and didn’t really pay attention to that i Just thought she was really cute …i got her home and she layyed down and fell asleep it was late so i didn’t mind. the next day i feed her normal food and water …plenty and she would Just sleep all lot the rest of the day. i took her to do her Business and i noticed she had bloody mucus looking with a cream colored looking worm …i took her to the vet later that day to get her checked up …the guy i got her from said she had all her shots but the vet told me she needed 2 more …..she said it looked like she had worms and gave me medication for the bloody poop and another to clear out all the worms ..and said to watch for any throwing up …in her office she gagged twice but nothing much really happened ….i took her home fed her her food and pills. she went to sleep. this morning she pooped normally i would say not much of the mucus looking blood except like 2 or 3 worm looking things i could see a bit. i feed her that morning as well as her pills ..i came back it was a mess she pooped with a strong odor and on her blanket as well …i noticed her pee had a strong odor as well the first day. i try playing with her but she Just puts her head down and goes to sleep …seems like she jus wants to sleep i tried walking her and she would not move a leg ..its hard to get her to do much ….all she seems to do is sleep . sorry for the long story but im worried she is a first pet of mine and im just worried something is wrong with her ….also would it be ok if i try walking her on a treadmill ? and what kind of toys can i get for her i don’t want to hurt her with some hard toy …thank you for ur time and hope u can help i really appreciate it