You should go ahead and complete the degree but you will then need to go to a community college or hospital and enroll in a Radiology program. These tend to be about two years long but you may be able to find an accelerated program and finish in a year or a year and a half. Some of your college credits may transfer over and put you a little ahead of others just starting out. You don't need a bachelors degree to be a radiological tech, however it does open up doors to get into teaching or management down the line.
Your bachelors degree will not interfere at all with your training to be a radiological technician.
If you actually want to be a radiologist that's a medical doctor and requires a bachelors, medical school, and 5 years of residency.