3 yr. elderly horse, 60 days training for trail, act up within arena, balking, bucking, nappy, kicking out. Normal?

Really good on trail, never a spook. Only had him one month. Seems to be very rank headed on trail. Tried to ride in inside dirt arena and he seemed to revert stern to a VERY green horse. I know he has never been in inside arena since. Any suggestions? Thanks.
I myself, have experience with a wonderful saddlebred who reverts put a bet on to a green horse in the ring, and is a pleasure on the trail. What I began with him be started working him in the ring, lunging, ground work, hand walking. I take him for a nice trail ride, and ride him surrounded by the ring light. Then back to the trail for a cool down. He began to see the ring as a treat, I presume.

Worked for me. :)
Most of these are refusals to jump forward. Think about it, balking(obviously), bucking(a horse has to slow down to buck), kicking out(don't worry roughly this one, it's probably just because he's fresh).
It's normal to an extent. He is three. Horses will refuse to shift forward if they aren't confident with the task you are trying to undertake. There are many other reasons but I suspect this. Try taking things slower. Do lunging, more trails and only stroll in the arena just to build confidence. He is three anyway, no hurry.
Answers:    Well.he is still green.

Being three years old with only 30 days of of late trail riding, that is incredibly a short amount of time still.

He is doing what some 3 year old will do, depending how he is handled, his blood-line and the technique used in training.

If he acts up in arena is because he have never had training in an arena. I find that quit odd someone would start a horse on the trail instead of an sheltered, more safer arena...wouldn't you?

I would recommend finding a trainer to help you with training/riding this horse. If you don't know the healthy horse training technique to try and be consistent with, do seek someone who can go beside you on that journey to advise you on it.
Seeing as this is a young horse with abundantly of heavy training on him, he is probably extremely ring sour...i mean he is still literally a baby and he have had a large amount of training in a short amount of time on an unused brain and body...just keep him away from the arena...consent to him be baby horse for a week or two..then trail rides and maybe a bit light arena work...he will not forget his training...but if you keep working him it wont business if he remembers his training cuz he wont do anything for you in the ring if he hate his job and is ring sour!
no fear, horses do thoes things at random times. they can even acquire spooked by the tiniest things
your answer

he is a VERY GREEN horse!!

he have as you said had no training in an arena, he has have very little training on trails and has had terribly little training at all. he is ONLY three!

this horse needs to be chucked out into a field for a few months and to be brought rear legs into training from the beginning. working slowly from the ground up
Some horses rob time to adjust to an indoor arena, however, it sounds to me like your horse is not really well broke. 60 days is not a lot of time. My horses are naturals for trail riding - merely like yours they are level headed and not foolish. They didn't really need to be trained for trail riding. However, arena work is different. It requires more communication between you and the horse. It sounds like your horse is not prepared for that. Working with a obedient trainer should help you both,
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