My veins are REALLY noticeable all of a sudden? HELP?

ummm so the veins on my right arm have always been noticeable u know where the nurses take the shots i guess for-arm yeah but it hasn't been THAT noticeable but lately the veins on my hands,my wrists,my for-arm on both arms have been very noticeable lately this morning i found them on my legs my skin is darkish like a bronze gold olive mixed in one im 13 lately i have not really been exercising which during school i used to work out 3-5 times a week um i have lost weight i think its because its summer and im not eating school lunch anymore but i have been on a healthier diet i guess since school ended i was 107 sometimes 108 now im 100 sometimes going as low as 97 sooooooooo i think that's it whats wrong with me??? o yeah my family does have history of blood disorders on my moms side and type 2 diabetes on my dads side could it be that i mean i think im a little young for that right??? HELP!!! :(