you tama cannot die from weight. That is why the max. is 99. It does not matter what weight it is so don't worry about it. Just make sure all hearts are filled and u will be fine. Don't forget to play with your tama some~times!!
Actually for a teen tamagotchi the best weight for it would be about 30 - 35 LB. And I'm pretty sure your tamagotchi can die from weight. But I'm not sure. Anywho if your tamagotchi goes over weight or atleast over the healthy limit for it's age then you should play jumping rope, This is a really usefull game because you get it as you first game on there (and mimic), Also it gives you some skill points and also makes your pets weight go down! I hope this information helped! Sorry if it's wrong but I'm kinda sure it's correct! *Puts throbbing fingers under the tap*.