Given you are 4.5 weeks out from your surgery, I would say it is unlikely your have caused any damage. I generally allow my patients to resume full activity after 4 weeks time.A thorough exam would help to see if your incisions are intact and make certain there is no internal bleeding, but ...
I agree with the previous answer, you should have the implant removed and allow your breast to heal without the extra tension that comes from a large implant.
Unfortunately, it is not rare that small open wounds appear after a breast lift with or without implants. Sometimes, it seems they take a long time to start healing, but then it will heal quite quickly, over a number of weeks. This should be followed closely by your plastic surgeon to make su...