I have low back pain, frequent urination, lower abdomen is hard, very tired, smells are strong, breasts are sore, and clear liquid can be squeezed out of nipples.

Maybe. Instead of asking online though, have you done a pregnancy test?

How late is your period? What was the result of the pregnancy test? When did you test? Have you tested?

Pregnancy can't be diagnosed by symptoms. You'll have to take a pregnancy test to find out if you're pregnant. Wait until your period is at least 2 weeks late, then test with first morning urine If that test is negative then wait until your next period is due. If that period is also missed, then test again or see your doctor for a blood test.

Sounds like pregnancy to me, or perhaps a UTI or maybe a flu issue.

Get the idea, no one can tell you or even guess from the "signs"
A missed period is one indicator but even it can be other things.

So you miss a period, wait 2 weeks and do a pregnancy test,
If that shows positive, then you are pregnant