I'm 5'0, what should my weight be?

Like average weight?

well I just looked this up and for a 5'0:
small frame( if you can wrap your index finger and thumb around your wrist and overlap the two fingers) = 104-115
medium frame( if you can wrap your index finger and thumb around your wrist and just touch them together) = 113-126
large frame ( if you wrap your fingers around your wrist and cannot touch them together)=122-137

hope this helps!

For an exact amount that you should weigh your BMI or Body Mass Index we would need to calculate to get the proper weight to height ratio that you are looking for. However I can tell you that for your age/height/weight you should be hitting between 100-120lbs for a healthy weight. There are factors that can alter these numbers, however for the average individual this would hold true.

how about but up a full body pic and ill tell you if your fat or not. that wood be simpler and more accurate.

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Probably 100 to 105 pounds would put you at the 50 percentile for your age and hgitht.

 
Average Teenager Weight

http://lifestyle.iloveindia.com/lounge/average-teenager-weight-236.html