Jimmy''s bipolarity

Hello everyone i have a staffy of tree months and a half named Jimmy I have him for 15 days and so far so good but there is something that worries me...he is a very smart puppy I have teach him to seat lay down give the paw and half the way to the stay
But he apart from the natural insctint of bitting everything wen I take him out he goes crazy with the leach bitting and pulling growling and if I want to touch him to calm him down he tries to bit me it lasts 10 minutes and than he goes back to normal and walks really good! Is this normal? Thank you and hope somebody can help me cause its the first time I have the breed and I'm scared that wen he bigger and stronger I can't hold him...

Sounds like first minutes out excess energy, you could use a chain lead for the first few minutes of the walk to stop him biting at the lead, distraction with treat or toys, maybe he will carry his favorite toy out on walks (my oldest boy does)

Buddy is 5 months old and although he doesn't do this when we are out walking he has a wild five minutes whilst I am trying to put his lead on - he also tries to bite when I try and get him but it is not aggression it is play -at three and half months your pup is not trying to bite you he is trying to play with you, as that is how pups play - staffies play very rough and tumble - try putting the lead on indoors for a ten minutes two or three times a day and get him to walk nicely and treat when he does - that way he will become used to the lead and associate good behaviour on it with a treat and wont get so excited when you put him on it to go out - he is still very young don't panic he will get used to the idea - a chain lead may help but be careful he doesn't hurt his teeth on it

Will try a chain lead and see how it goes...about the exesse energy I don't think so cause he does it also on the middle of the walk or just going home its a crazy this one he just snaps pulls growling and then 10 minutes after its jus like nothing happened
Going to try your suggestions and report the progresse hopefully

He's still very young so won't be aggression and is more likely to be excessive play as already mentioned. Being Smart you could ask him to sit when he does this and not move until he does by which time he will have forgotten why he wanted to play so rough.

When you get a min, pop along to this link and say hi:-
https://staffy-bull-terrier.niceboard.com/f7-new-member-introductions

I'm sure it will work itself out - staffies are lovely dogs if not some what mad....Buddy quite often has mad ten minutes where he runs around like a looney knocking anything in his way over - if you try and get him he tries to bite then he suddenly just stops as if he never did anything and sits down with a toy- loveable but odd!

I'd also put the lead on throughout the day so he gets used to it. Suki was that way with her harness as well. It's not a natural thing for them and it takes getting used to