Is 650cc too big for my build?! I am 5’5 1/2, I weigh 155lbs. (Photo)

Without examining you it is difficult to give good advice in this respect. Implants should be chosen based on specific measurements of your body and chest. Depending on your base-width 650 cc silicone implants may or may not be appropriate. Your surgeon should have measured you at a consultation and provide a selection of implants that will fit your frame to try on. You should then have had a formal sizing session which should show you immediately whether the implants look right on you or if they'll be too big. If you are already scheduled for surgery and these questions are still outstanding then you should really speak with your surgeon and get them answered. Best of luck with your procedure 

Thank you for the question and pictures.  Based on your photograph, I think that you are starting at a good place and should have a very nice outcome with breast augmentation surgery.  My best advice: more communication.
It is definitely worth spending more time (prior to the date of surgery) with your plastic surgeon to discuss further.  As you know, it will be important for many reasons, that you feel comfortable that you and your plastic surgeon are on the "same page" prior to proceeding.

  Generally speaking, the best online advice I can give to ladies who are considering breast augmentation surgery (regarding breast implant size/profile selection) is:
1. Concentrate on choosing your plastic surgeon carefully. Concentrate on appropriate training, certification, and the ability of the plastic surgeon to achieve the results you are looking for. ***Ask to see lots of examples of his/her work. Sometimes, it is necessary to seek several consultations before you feel comfortable about your choice.
2. Have a full discussion and communication regarding your desired goals with your plastic surgeon. This communication will be critical in determining breast implant size/type/profile will most likely help achieve your goals. 
In my practice, the use of photographs of “goal” pictures (and breasts that are too big or too small) is very helpful. I have found that the use of words such as “natural” or "D or DD cup” or "look extremely big" etc may mean different things to different people and therefore prove unhelpful.
Also, as you know, cup size varies depending on him who makes the bra; therefore, discussing desired cup size may also be inaccurate. Again, best not to discuss your goals and/or judge the outcome of the procedure performed based on achieving a specific cup size. The use of computer imaging may be very helpful during the communication process. The use of in bra sizers may also be helpful. In other words, use as many “visual aids” as possible during the communication process. I encourage patients to meet with me as my times as necessary, to feel comfortable that we are both on the “same page”.
3. Once you feel you have communicated your goals clearly, allow your plastic surgeon to use his/her years of experience/judgment to choose the breast implant size/profile that will best meet your goals. Again, in my practice, this decision is usually made during surgery. I generally select appropriate breast implant size/profile after the use of temporary intraoperative sizers and viewing the patient's chest in the upright and supine positions.
 One question that might be helpful for you to consider: would you be more disappointed if you are slightly too big or slightly too small after the breast augmentation procedure?
I hope this helps. Best wishes for an outcome that you will be very pleased with.