Can pregnancy symptoms start before a positive test?

[tulipsandteacups]

I had unprotected sex with my partner last Sunday, a few days before I ovulated.

Since yesterday I have experienced unbelievable tiredness. 3 naps today and slept 13 hours last night. VERY unlike me who usually has 7 every night and not a minute more,

My nipples are slightly sensitive too,

I took a test today but it's negative ....

Can symptoms start before a test shows positive? I assumed that if the hormones are high enough to create symptoms then surely they would be high enough to make a test positive ....

Any advice?

I think honestly it can work either way.
With my last pregnancy I knew before I got a positive, however this month I had every symptom you can think of including new ones for me and af still arrived on time. You won't know until you get that bfp or af arrives unfortunately!
Also recently the week leading up to my periods I have been ridiculously tired too, so maybe normal for that stage of the cycle?

If you had unprotected sex on 16th and ovulated a few days later, around 19th it's only been three days, it can take 7/8 for implantation to happen and still a few days after for hcg to rise, if you have a fertilised embryo it won't have even implanted yet
Perhaps you're coming down with something? Maybe you need your iron levels or vitamin d checking

Yes they can. I only ever have vivid dream (nightmares) when pregnant and I start having them at like 2/3dpo. Any other cycle I dont

Very much so! I tested because I felt awful, negative. A week later, still feeling awful, tested again because I was getting worried there was something wrong with me and there was a positive clear as day!!! Same thing happened with my other two, symptoms a good week before a positive 🤷🏼‍♀️

It's more likely to be a virus

Definitely. With both my pregnancies I felt cramping before a positive test. I assume this was implantation as I also experienced a small amount of spotting. I had slight dizzy spells and very vivid dreams.