First, do NOT give up. There is plenty of time for improvement, and you will get that TEAS score you need! Promise!
I jumped in and took the TEAS about 1 month after finishing AP1&2 and micro, without studying for it and surprisingly pulled a 94. That is not at all meant to be a brag, but a statement of how important it is to take the test right after you finish the material. I would recommend taking your third one as soon as you finish out either taking AP (not so much micro, there wasn't anything on micro) OR after studying AP.
Breaking it down by section:
English-- someone already mentioned the Momentrix material. I'm studying for my second go at the TEAS, and if you just type in "Momentrix English study guide" into google it will bring you to a YouTube video about 1:20:00 long. There is so much information in there, but its quick and a HUGE refresher. I also went along with the people talking in the videos and googled the topics I didn't know and found a middle school/high school lesson and worksheet to go with it, and practiced right after watching the mini lesson from Momentrix. Key things to focus on there would be compound/complex sentences and punctuation.
Reading-- this was seriously the worst if you're not fabulous at reading. I personally am not and this was my worst section. For this, the PocketPrep app (which is free, but of course has the option to buy) has some short passages and big picture questions that get you into the right frame of mind for answering reading questions. I would buy the full version bc its honestly been SO helpful for the reading and english sections! (its about $25, but there is a middle pricepoint too).
Math-- the ATI study manual 6th edition (gray cover) has all you need for the math section, and YouTube what you don't know. I got 100 in this section on my first test, so i'm sorry I am no help with this part.
Science-- This is the section I'm giving all my effort to for round 2. I want that 100 this time! As someone previously mentioned Crash Course and Khan Academy are great resources for this part, but I think even those are slightly too in depth for the scope of the TEAS. I thought this section would be harder than what it was. Breathe thru the science, it's broad but shallow. Since I don't know what classes you've already taken, I wouldn't mind sharing the notes I took over AP1 and 2 with you if that's something you want! I really think that since those classes were fresh, and I took the notes that I did, it really gave an advantage taking the Test.
Overall, I think the ATI manual alone is a waste except for the math. It doesn't tell you what you need to know other than "here, know all of this" but without giving you the "this". Youtube is the best thing ever and the internet has all you need to find information out!
I BELIEVE IN YOU!!!!! also caffeine pills. go get them.