I did exactly what you did. I started with a pap motor and reflex wing. Nearly killed myself - so I'm speaking from experience. £1000 worth of damage and a good few scars to match. So, I then sat back and reflected a bit. If your motor cuts out, you are free flying, paragliding. You need to know what you are doing. Paramotoring has no governing body (unlike paragliding - stupid I know) - you can literally do as you have done, buy the kit on ebay and take a run in a field and go flying. But, do you really want to be at 2000ft when you get an asymmetric collapse and not know what to do? Or stumble across a cunim that sucks you up and up - and not know how to descend? Or even stray into airspace and who knows what?!?
Obviously, many people have done this on their own back and been absolutely fine. In fact, some of the worlds finish paramotor pilots did exactly that. But it doesn't always go to plan. Many people have died. The fact it it unregulated, also means 'instructors' pop up out of know where. These have also been responsible for many deaths and or broken backs/bones/lives!
By all means give me a call
I can point you in the right direction... even if it is straight into the motor side, I can recommend some very good people.
Ta very muchly and good luck and safe flying,
Ben