Is this a bad time to test?

Me and my husband have been TTC for three months now. I have a regular 28-day cycle so for the past couple months I have been fairly predictable. I always get sharp lower abdomen and pelvic pains the day before I start my period, and I didn't get those yesterday. Today I should be starting but I have yet to have any pains or spotting (which I usually have also). I have very high hopes that this might be the month, but I do not want to waste money on tests. I know it is not too early to test, but my question is this: If you do not test in the morning, am I likely to get a false positive? I have drank other fluids today, and I have also had unprotected ...will these things possibly weaken my chance of a BFP? Thanks for any information!