I have a mountain bike with road tires, which I've use for commuting almost every day for over a year now but had barely used for the many years before. It has recently (~1.5 months ago) been serviced, which involved the brakes being adjusted and something being replaced due to damage which I believe was the headset, but I can't be sure because I just agreed to replace what was necessary and the conversation was not in my native language.
Before the service my bike was always a bit wobbly, but I always thought it was normal. Afterwards I realised why other people have to make so much less effort to balance when making hand signals.
At some point after the service my front tire seemed to be going down very quickly, but after checking for punctures and finding nothing I put the tube back in and the tire has held pressure well since. The problem is, since then I feel like I am constantly cycling with a flat despite the pressure being right, and my bike seems wobblier than ever before. I don't know whether I did something wrong when I checked the tire (never done it before) or whether it is something completely different.
Can anyone help?