My first biologic was Remicade. After 6 infusions, rheumy and I called it a failed experiment. After the loading doses, which might have had a tiny amount of success, he was gradually increasing each dose by one vial each time till the last dose was 8mg/kg. At that dose, which did not do anything positive, the side-effects kept me of work the next day as I felt like I had flu. Then it was on to Enbrel, which worked for a day or two after the injection (weekly). Then I asked if doing the twice/weekly dosing would help and he agreed to try it. That was my introduction to pre-filled syringes. Now I will only use pre-filled syringes when available (long-winded reason omitted). It was successful despite the lower dose per shot. Weekly dosage is the same. It was stopped when we thought it wasn't working any longer, roughly 9 months after starting it. In hindsight, this was probably a huge flare rather than the drug not working any longer.
Then came Simponi, which never quite lasted for a month. Gave it up after 8-9 months. Then came Humira, which decreased my WBC so far that rheumy stopped it. It made me sad because that drug was probably the most successful biologic I've ever used.
Then came Cimzia. Stayed on it for 2.5 yrs. It worked early on but I had a flare in early winter (roughly the same time as when I was on Enbrel). Since at the time there were no others to try, I stayed with it and after 3-4 months, that flare eased and it was back to working well again. I only stopped when I had a case of pneumonia. When my PCP had me get a chest x-ray to make sure I was cleared up after the antibiotics were finished, the x-ray showed a nodule. It took quite a while to get that worked up and about the time I was going to be cleared to get back to the Cimzia, I fell and broke 8 bones in my foot. Took a long time to heal and I opted to go to Cosentyx for the next med (hubby was irrationally worried about me being on a biologic at the time, but he's eased up on that worry now that he's on a biologic also for PsA!).
Cosentyx worked but caused me a lot of gut issues and I gave it up after 4 months and went back to Cimzia. I've taken 2 of the loading doses.
In answer to your questions--thankfully I had better success after the first one. And better results after the first successful one. If for some reason Cimzia does not work as well as it did the first time, I think I'll try Enbrel again before moving to something new. Personally, I think it's a crap shoot as to whether one of them will work or not. This is for PsA and I've been on MTX through all of these biologics.
Like is said above, sometimes we need to wallow. Sometimes we just have to trust that it will all work out. Sometimes we don't know what we should do and just take something on the hope that it will work for us and that if it doesn't, there are other choices. Hope you find the med that works for you and have the strength to get up the next day to try again.