UTI versus STI/STD?

Hi, 

Just looking for some honest advice/opinions. I’m a healthy and active 31 year old male. Straight, bi curious perhaps. I’m almost always safe with sex, but had an encounter I’m concerned about. Facts... 

-One week ago I hooked up with a girl I don’t know well at a bar. She went down on me for 3-4 minutes. That’s all. 

-8 days ago I was a little drunk and used a butt plug on myself for fun. Honestly, I hadn’t cleaned it after the last use on myself. Dumb idea (and thus the bi curious part). 

-I had a monogamous partner before 8 days ago and we were both tested and didn’t have any std’s. 

Current symptoms: some urethral irritation, bad and frequent diarea, frequent need to urinate, some bloating. 

I had an STD panel done today and am awaiting results. I have had a UTI in the past, unrelated to sex. Also have had a prostate infection, unrelated to sex (because it was before I was having sex). 

Chances this is a UTI related to e coli or something else? Chances I did get an STI? 

Thank you in advance. I’m awaiting the std panel results, I just wanted additional feedback. 

How long are the symptoms after exposure.

Some STDs need more than 1 or 3 to be detected.