Despite having a Canyon Grail gravel bike for years, I am just starting to learn to do my own bike maintenance. I made the mistake of letting the brake pads go unchanged for far too long and ended up needing to replace the brake pads, and rotor; in trying to change them myself I made the mistake of tapping the brakes mid-change and letting all the hydraulic brake fluid (mineral oil, in the case of my Shimano GRX set) out of my rear brakes.

I went to Market Street Cycles for a brake bleed and $180 later (it included a tune up) I got my bike back. But, while I can slow myself down, it takes a good 10-15 ft to fully stop myself from a moderate speed (10mph?) using my rear brakes, and I have to squeeze pretty darn hard. The front brakes feel weaker as well but the Market Street Cycles guy says he didn't touch the fluid there, just changed the pads (new resin brake pads; not sure what I had before). He also says the pads need to break in a bit.

Is it normal to feel it takes slightly too long to stop when going down a hill?? I feel like the brake bleed was not done super well (from friends/google, there may be air bubbles in it)? The guy said to come in next week to get them re-bled. Do you know if this is something he should charge me for again, or if they should re-do it for free since I feel like it was not done correctly the first time? Also, a former bike shop said they reconfigured my hydraulic brakes for "short pull" instead of "long pull" making them WAY more responsive. The Market Street Cycles didn't know what I was talking about when I asked if he could do the same.

Lastly, is this something I could learn to do at the SF Bike Kitchen, for anyone with experience there? That is, replace rotor, brake pads, do a brake bleed, change out a chain, etc. I assume yes for chain and pads, not sure about the others. Thanks in advance!