5DPO - twinging in lower abdomen?

Not consistent, but yesterday I've was utterly exhausted. Like an exhaustion I've never felt before. Headache, congestion/runny nose, and so gassy. Yesterday and today I have had random twinges in my abdomen. Low,  near my right ovary. Occasional cramping. Normal? Could just be getting actually sick? Or possibly implantation? This is only my third month of trying, so I'm still trying to figure my body out lol.