When is a good time to take a pregnant test ??

So me an my SO are TTC we've been trying for three months now , but I'm the type of person that's not worried Bout having baby's i mean I'd love to but to me if it happens it happens type thing lol anyways I usually feel like I know when I'm getting my period on glow it say I should get it on Friday but I don't think I'll be getting it usually NY period comes a Lil early before glows predict or a day or two after , anyways I've been really sleepy lately like I go for my 30min walks at least four times a week every time when I'm finish I feel so tired and go to sleep which is weird my partner thinks my boobs are huge n my nipples a slightly darker then normal , ATM im to scared to take a test as we've had a fasle negative before and that hurt my partner as he wants us to make a family , so girls please help !!!