Clomid and provera question

MamaKass
Okay I have a question. I haven't been tracking my period in my app because I've been trying not to stress myself out and just taking ovulation tests. Anyways, I just got prescribed provera and clomid since I am not ovulating on my own, will it really cause a difference if I take it say CD 25 or 26 instead of CD 28? Last time I was on it it took me 10 days to start a period anyways. I don't want to ruin this cycle though as it's going to be my first clomid cycle.I feel like it wouldn't be a big deal since I'm not going to ovulate and some people have 21 day cycles anyways.