First, who's decision was it to get PEP? Was it yours or a faculty member? The viral load was undetectable, so I am not really understanding why you are freaking out. Undetectable means noninfectious (for all practical purposes) with regards to HIV. I wouldn't worry about it personally, but do what you have to do to make yourself feel better.
Here is IU's post-exposure plan if you are interested. HIV is discussed on page 21 of the document.
http://www.ehs.indiana.edu/em/IU Bloodborne Pathogen Exposure Control Plan.pdf
EDIT: Appendix C (pg 47 ish) is more specific regarding procedures.
"
IF THE SOURCE PATIENT HAS AIDS OR OTHER EVIDENCE OF HIV INFECTION,
DECLINES TESTING, OR HAS A POSITIVE TEST, THE EMPLOYEE SHOULD BE
EVALUATED CLINICALLY AND SEROLOGICALLY FOR EVIDENCE OF HIV
INFECTION AS SOON AS POSSIBLE AFTER THE EXPOSURE, AND, IF
SERONEGATIVE, RETESTED AFTER 6 WEEKS AND ON A PERIODIC BASIS
THEREAFTER (e.g. 3, 6, AND 12 MONTHS) FOLLOWING EXPOSURE, TO DETERMINE
IF TRANSMISSION HAS OCCURED.
The employee will be informed of prophylactic AZT therapy as a treatment option. If the
employee desires AZT, this will be administered in consultation with the I.U. Health Center.
During this follow-up period, especially the first 6-12 weeks, when most infected persons are
expected to seroconvert, exposed employees should receive counseling about the risk for
infection and to help them follow U.S. Public Health Service (PHS) recommendations for
preventing transmission of HIV.
If the source patient is seronegative and has no other evidence
of HIV infection, no further follow-up of the employee is necessary. If the source patient cannot
be identified, decisions regarding appropriate follow-up should be individualized based on the
type of exposure and the likelihood that the patient was infected.