Breast augmentation issue
Some bruising is normal after breast augmentation, and swelling is normal. As for a bra,, may surgeons do not even use them. Even if your surgeon's office is closed until Monday, I am sure you can get in touch with the surgeon or a covering doctor to ask questions.
Your symptoms are likely part of the healing process
Am I correct that your questions come pretty much immediately post-op? If so, it appears that your issues are part of the normal healing process. Bruising after breast augmentation is not uncommon, especially along the bra line. Similarly, swelling in the underarm area is also common as 85% of the breast is drained in this area. This may also result in funny feelings you describe in the underarm. Generally, these issues resolve 2-3 weeks after surgery. In my practice, surgical bras or wire bras are not necessary after surgery. Coobie bras are my standard. I know that some other surgeons still recommend special bras. As for your final concerns, shooting pains, sensitive nipples, and achiness are all within normal limits of the usual postoperative implant patient. I know it can be difficult, but try not to worry. If your concerns persist, reach out to your surgeon. The surgeon and the doctor are there to help.