advice, thoughts and past experiences

I ovulated on 26th or 27th, based on my clear blue opk. I experienced mild cramping on 26th and so I think this is the day I ovulated. There is a high chance that I conceived based on the times I had inrercourse leading up to this date. It is now 3-4 DPO and I'm experiencing severe lower back and mild pelvic pain on my left side. What are people's thoughts on this? Is this an early indicator that I have conceived? Or is this something I need to be concerned about? The pain resorted me to tears earlier today, I'm struggling to stand and bend down and walk due to the lower back pain rather than the mild pelvic pain. Any comments will be much appreciated 😊 thanks!