tablet problems

I bought a samsung galaxy3 and used it for maybe a week or so and some strange things started to happen... For example the camera would stop working until i reset the device and that happened a few times to me. Maybe 3 or 4 days later i use it and for some odd reason it shut itself off and then when i would turn it back on the date and time were reset to 00:00 Janurary 1st but kept all my apps and information so i fixed it but it happened again... it happened 3 times sense yesterday so i dont know if you can help me in anyway but worst comes to worst il just return it....... one last problem i had as well is i couldnt connect to the store and certain things but i could for others i dont if its my connection or not so if you could help please do... thank you.