When can I test?

Hello ladies! I am getting so impatient and I want to know when I can take a test. I bought a Clearblue Digital with Week Estimator test today, but I want to know if I can take it with my First Morning Urine first thing in the morning or if I should wait. According to ovulation tests I am currently 10 dpo (ovulated the 12th). Wednesday evening I had some cramping, it was definitely in the uterine area. Lasted the night but faded by morning. I assumed I was just going to have an early period since my periods have been a bit wacky in the past. But I haven't had any more cramps since Wednesday and still no period. I am due for my period, according to a normal cycle for me, on Tuesday (the 26th). I want to take one this weekend, if possible because I am starting a gym routine with a friend on Monday, and I'd like to know if I should avoid weight training or not.... With this Clearblue Digital test how soon can I test, with accuracy?