3 Tickets, Exhaust, Tint, 4-ways

[BlkWhtTSI]

So the other day I got pulled over by a parked PA state trooper on 422w. When i passed the trooper, my windows were about 50% down, i was directly next to a semi-truck, and behind another vehicle in the passing lane. The trooper pulled me over and said the reason for the stop was my dark tint and my loud exhaust. The trooper took a tint reading which read 28%. He went back to his vehicle and was there for 20-25 minutes. When he came back he had 3 tickets 1 for tint, 1 for the exhaust, and one for not putting my 4-ways on.
My questions are:
1. Since I was next to an accelerating semi-truck I do not understand how the officer could have determined that my car was too loud. No decibel test was performed to truly determine how loud the car is. Could the ticket still stand after these two points?

2. As you can see, DSMRob is visible in the car, this photo was taken at 7:30pm by the way.
https://www.flickr.com/photos/455320...n/photostream/
Here is a picture at 8am
https://www.flickr.com/photos/455320...n/photostream/
Since it is visible inside the car, will these photos be useful in court to reduce or lift the ticket?

3. I have never gotten ticketed for not putting my 4-ways on (never put them on for a stop before). Is that really a law to put the 4-ways on when pulled over?

4. I plead not guilty and sent in the checks for the total plus $8 for each ticket like it says. However, today i received 2 new tickets for the 4-ways and exhaust for $35 more than what they were originally. Why could that be? Am I now liable for another $70 on top of the money I already paid?