Mazal tov on your wedding!
Based on what you write, that you have already had several full acts of relations without any sign of dam betulim (hymenal bleeding), this might be treated as dam makkah, bleeding from trauma. Dam makkah does not make a woman niddah, even if it did come from the hymen.
However, in order to establish that this is dam makkah, you need to be able to identify what is causing the bleeding. We suggest inspecting yourself physically using a mirror, and/or consulting your physician or a bodeket taharah. Once someone has visually identified the source of bleeding, no further steps need be taken other than precautions to enable you to heal.
If no external cause can be found, then please get back to us with details.
Please write back with any further questions.