What will happen if i take an extra b-12, vitamin d, and vitamin e?

Vitamin B/D/E: If you are eating a healthy, well-balanced diet, you probably don't need to take vitamin supplements. Regarding your question, B-12 is water-soluble and therefore if you take excess amount, you will excrete it in the urine. However, fat-soluble vitamins (A,D,E,K) can be toxic if taken in excess. Recommend discussion with your primary care physician before embarking on vitamin supplementation.