Doesnt sound like they're after you. Like they'd spend all that money getting a heli to keep tabs on you. Unless your in the mafia or supplying terrorist with anti aircraft RPG's they wont bother.

I had a police heli follow me for a mile walking once, from my mates to my house. Then it stayed around my house for about half hour. I went out to the snooker club and found out someone had their car nicked and the discription was the same as me. And i was wearing the same colour clothes.