After 6 weeks sitting in the wet weather, for sure you will get some rust on your break disc.
If you didn't rise your vehicle, your tires are not in perfect circle neither.
They will result the vibration feeling that you have right now.
If it won't go away after few days driving, you may need to pay close attention then.
BTW, the description of your vehicle's condition with Year/Make/Model will always help yourself to get better answer.