Oh good !! When my Chanel had coccidia she never collapsed but did get lethargic.....She was a tiny tiny thing like Bazter and I freaked - I was lucky to get her to the ER before she got really bad so I totally understand how fast they can go down
you did really great getting him to the vet as soon as you did - you saved his life you know...Coccidia causes such severe dehydration that they can go into shock and convulsions....
ALL THE BEST TO Baxter !! Sounds like he'll do great under your care and it's worth it to keep a very close eye on him at that age...Good luck and keep us posted ok ?