advice needed and or opinions please

Lacey

so I'm on cycle day 21. no idea when I ovulated but this morning I woke up and thought I was going to be sick. went to the toilet but nothing. felt lightheaded and really dizzy. I also have some cramping. it's really weird like almost feels like a pulled muscle. I've also have some brown discharge/spotting. could this be implantation? I feel really unwell! don't know what to think and when to possibly test? tia