Fertility aid ADVICE NEEDED???? 😭

My doc prescribed clomid 100mg for CD's 8-12 because my cycle is so long. Im on CD 13 and feel really really weird, my lower stomach/pelvic area feels really heavy and my breasts are sore. Before clomid i was using folic acid for 3 months then pregnacare conception for a few weeks then i was prescribed clomid and took my last pill last night and i am using preseed alongside the clomid every day of my cycle. I have not took one single pregnancy test because i just dont want to break down if it comes back negative it is soul wrenching. I could be pregnant right now and wouldnt know. When should i test???? Im so afraid 😭